FOUS11 KWBC 111942
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
242 PM EST Sun Jan 11 2026

Valid 00Z Mon Jan 12 2026 - 00Z Thu Jan 15 2026


...Central Appalachians...
Day 1...

Snow squalls are expected to wane by this evening over the Mid-
Atlantic as the associated cold front exits into the eastern
Atlantic Ocean and lapse rates weaken following sunset. Upslope
northwesterly flow into the terrain of the central Appalachians may
continue to produce moderate snowfall until early Monday morning
when this flow eventually weakens and dries out due to a more
westerly component to the winds. A few inches of additional
snowfall are likely across the Allegheny Mts of WV, western MD, and
southwest PA.


...Great Lakes & Northern New England...
Days 1-3...

Deep upper trough and attached closed low starts the period over
New England with an associated rapidly deepening surface low
quickly exiting towards Newfoundland. Lingering light to moderate
snowfall is possible tonight along with increasing winds across far
northern ME due to this area of low pressure. Latest WSSI depicts
Minor Impacts through tonight due to this continuing snowfall.

Meanwhile, cold northwesterly flow will weaken on Monday over the
Great Lakes and northern New England as an embedded shortwave
crosses the region with additional light snow downwind of Lake
Ontario and into the favorable upslope terrain of the Adirondacks,
northern Greens and Whites. Then by Tuesday a much stronger
shortwave and area of low pressure is expected to pass over or just
to the north of the Great Lakes. Initial WAA snow is possible over
the Upper Great Lakes Tuesday morning along with a glaze of
freezing rain, but snow and ice amounts are expected to remain
light. As this system exits to the east on Wednesday and upper
troughing deepens over the Great Lakes as well as increasing
northerly CAA, lake effect snow is forecast to pick up once again
along the shores of Lake Superior in the U.P. of MI.

For the entire period snowfall totals are expected to remain
mostly light outside of the Tug Hill Plateau and favorable
snowbelts in the U.P. of MI. WPC probabilities for over 8" of snow
through 00Z Thursday are 50-70% in the Tug Hill and 20-50% in the
MI U.P. from the Porcupine to Huron Mts.


Snell


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FOUS11 KWBC 120808
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
308 AM EST Mon Jan 12 2026

Valid 12Z Mon Jan 12 2026 - 12Z Thu Jan 15 2026


...Great Lakes...
Days 1-3...

Ongoing westerly flow over Lake Ontario will keep additional heavy
snowfall of 6-12" in the forecast today over the Tug Hill Plateau,
while minor amounts generally between 1-4" occurs around the
Buffalo area and the Adirondacks. By tonight, a Canadian clipper
system will race east over southern Ontario with just enough low-
level WAA and a plume of 700-300mb moisture aloft to support a
brief overrunning setup over the MN Arrowhead, northern WI, and the
western MI U.P.. Ice accumulations are likely to be less than a
tenth of an inch, but WPC probabilities show moderate chances

50%) for ice accumulations over on-ehundreth of an inch. Slick

spots on untreated surfaces are possible Monday night and into
Tuesday morning in affected areas.

As the clipper continues to advance east into southeast Canada, a
robust 500mb vorticity max diving south will accompany a strong
cold front that induces strong CAA over Lake Superior Tuesday
night. Snow will increase in intensity over the Michigan U.P. as
surface-850mb delta Ts dramatically increase and low-level lapse
rates sharpen. The upper-level trough continues to dive south
through the Great Lakes on Wednesday and the same CAA regime will
race south over Lake Michigan. Guidance is coming into better
agreement on the formation of a potent single-band LES setup
producing a swath of heavy snow over northwest IN that could
oscillate at times to as far west as the WI/IL lake shores and as
far east as southwest MI. Meanwhile, much of Michigan's Mitten will
contend with multi-band lake effect streamers as a surface trough
pivots over the Great Lakes Wednesday and into Wednesday night.
This same trough axis, along with the CAA over the Great Lakes,
will trigger lake-enhanced snowfall over northern OH, northwest PA,
and western NY by early Thursday morning. Snowfall will become
more synoptically-enhanced by early Thursday morning as a 700mb low
tracks over Lake Erie and would support heavy snowfall into the
day on Thursday as well.

24-hour WPC probabilities through 12Z Wednesday show
moderate chances (40-60%) for snowfall totals >6" along the
Keweenaw Peninsula and both the Huron and Porcupine Mountains of
the MI U.P.. 24-hour probabilities through 12Z Thursday depict
northwest IN as having moderate chances (40-60%) for snowfall
totals >6". Note that should 1-2"/hr rates materialize, localized
amounts approaching a foot of snow are possible. Lastly, through
12z Thursday, the first 6-12 hours of the impending winter storm
show low chances (10-30%) for snowfall totals >4", but with the
storm likely to produce additional heavy snow along the Chautauqua
Ridge and into western NY, expect heavier snowfall totals to
envelop these areas through Thursday. The WSSI-P currently shows moderate-to-high chances (50-70%) for at least Minor Impacts over
northwest IN, northeast OH, and western NY through Thursday
morning.

...Upper Ohio Valley, Central Appalachians, & Northeast...
Days 3-3.5...

A robust 500mb shortwave trough over the Upper Midwest will race
southeast toward the Ohio Valley Wednesday night. There remains a
fair amount of uncertainty and model spread that is making this
forecast tough in the Ohio Valley and as far east as the I-95
corridor, but the higher confidence areas are the spine of the
Appalachians. As the 500mb shortwave deepens into a closed upper
low Wednesday night, an accompanying strong cold front will
collide with the central Appalachians with strong 925-700mb layer
CAA. The combination of brisk NWrly flow and excellent PVA aloft
ahead of the upper low will produce heavy snowfall rates from the
Laurel Highlands of southern PA on south to the Blue Ridge and
Smokey Mountains. Snow is likely to continue beyond the scope of
this short-term discussion as cyclonic flow around the western
flank of the storm system sustains favorable upslope flow into the
central Appalachians. The WSSI-P is showing >50% chances for a
at least Minor Impacts over the Smokeys of TN/NC, and both the
windward slopes and peaks of the central Appalachians. Residents
and travelers should plan for a disruptive snow event in central
Appalachians Wednesday evening and into Thursday.

From the Ohio Valley on north through western PA and into the
Northeast the forecast is more murky. Guidance across the board
shows different evolutions and tracks of the aforementioned 500mb
low. The CMC shows a lack of deepening/phasing of 500mb vort
maxima that keeps the synoptic-scale forcing limited. The ECMWF/EC-
AIFS/UKMET camps show a closed low by tracking across the lower
Great Lakes and into the Northeast. To illustrate the ongoing
changes, the 00Z ECMWF from 24 hours ago had a closed low south of
Louisville, KY by 12Z Thursday, while the latest 00Z ECMWF has the
closed low near Cleveland, OH at the same time Thursday. Lastly,
the GFS/GEFS is farther south over the OH Valley that then heads
for the Mid-Atlantic coast as a weakening closed low. All these
evolutions lead to different snowfall footprints, particularly
along the I-95 corridor and northern Mid-Atlantic. No matter the
track of the upper-low, the meteorology involved supports periods
of snow north of the emerging 700mb low. The EPS/GEFS both show the
left-exit region of a strengthening jet streak off the southeast
coast being placed over the Northeast, which also pairs favorably
with 700mb Q-vector convergence on both GFS and ECMWF solutions
over the eastern Great Lakes and interior Northeast. Through 12Z
Thursday, WPC probabilities show northern OH (including the
Cleveland metro) on north and east along the Chautauqua Ridge and
the Adirondacks showing low-to-moderate chances (30-50%) for >4" of
snowfall.

Residents and travelers across the Northeast will want to monitor
the forecast closely in the coming days as this complex forecast is
likely to change in the coming days. The lowest confidence in terms
of snowfall amounts and impacts are along the I-95 corridor as
potential scenarios range from a significant winter storm for areas
along I-95 in southern New England to minor snow accumulations at
most depending upon the strength and track of the approaching
upper-low. Not only are amounts unclear, but boundary layer
temperatures at the onset Wednesday night and early Thursday
morning would support rain as the initial precipitation type before
changing over to snow. For now, the spine of the Appalachians are
favored to see accumulating snowfall late Wednesday into Thursday.


Mullinax





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FOUS11 KWBC 121909
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
209 PM EST Mon Jan 12 2026

Valid 00Z Tue Jan 13 2026 - 00Z Fri Jan 16 2026


...Great Lakes...
Days 1-3...

Slowly amplifying flow across the east will result in periods of
light synoptic snow, and more impressive lake effect snow (LES)
through the period.

Tonight, a surface trough will track rapidly eastward across the
eastern Great Lakes and into New England while weakening. Although
this feature is progressive and of modest intensity, the enhanced south-westerly flow in its wake will help spawn LES, especially
downwind of Lakes Erie and Ontario through Tuesday morning. Slowly
rising heights within shortwave ridging Tuesday morning will bring
a quick end to this LES, but at least briefly heavy snow rates of
1"/hr (10-20% chance) will produce significant accumulations,
especially in the Tug Hill Plateau where WPC probabilities are
moderate (50-70%) for at least 4" of snow.

Thereafter, a series of fast-moving shortwave troughs will track
southeast downstream of an amplifying ridge across the western
CONUS. This will lead to a gradually deepening trough in the east,
with increasing cold advection within impressive cyclonic flow. The
first of these shortwaves will track across MI and into northern
New England late D1 into D2, pushing a surface low along the
US/Canada border through Wednesday. Some modest WAA will spread
light synoptically forced snow from WI into MI, but with only
modest accumulations.

More impressively, this low will drag an arctic cold front
southward behind it, aided by a secondary impulse which will track
towards the Gulf Coast helping to deepen the longwave trough with a
closed low over the Great Lakes. While there has been a lot of
uncertainty and latitudinal changes with this evolution the past
few model runs, impressive CAA behind this front will result in
impressive LES, especially in the north-wind lake effect belts
across the U.P., northern L.P., and south of Lake Michigan, with
additional LES likely into northeast Ohio and the Chautauqua Ridge
during D3. WPC probabilities for more than 4" of snow D2 reach
50-70% for parts of the U.P., and then expand to southeast of Lakes
Erie and Ontario D3, with the most significant snowfall likely in a
single band southeast of Lake Michigan (with possible Lake Superior
connection) across northern IN where 8+ inches of snow is possible
(30-50% chance).


...Central Appalachians through the Northeast...
Day 3...

Amplification of the mid-level pattern through Thursday will result
in an anomalous trough digging across the eastern CONUS, reflected
by NAEFS 500-700mb heights falling below the 0.5 percentile across
portions of the Mid-South and Southeast before 00Z Friday. While
this trough is impressive, there has been considerable variability
over the past several model cycles both in terms of the intensity
and placement of the core of this trough, most notably with the
position of the closed low likely to develop Thursday morning.

This closed low will manifest from a deepening shortwave tracking
almost due south out of Manitoba, while secondary energy rotates
towards the Gulf Coast. Together, these will amplify the trough as
noted above, with the lead shortwave closing off and forcing a
slightly negative tilt by the end of the forecast period. At the
same time, a powerful jet streak will arc increasingly poleward
over the Atlantic (downstream of this trough axis) to provide
intense left-exit diffluence overlapping the impressive mid-level
height falls and divergence. While this should support a deepening
surface low pressure, guidance has systematically backed off on the
intensity and southern latitude of this low, with any secondary low
development occurring too far east to bring heavy
snowfall/precipitation to the east coast despite the lead low
moving across northern New England.

The cluster analysis (00z/11 cycle) indicates that the GEFS is
likely underdispersive into D4 as 77% of its members make up one
cluster, which is also the most amplified and slowest due to
extremely different ridging intensity over northern Ontario. While
this solution can't be ruled out entirely, the trend in the GFS
heights combined with the more broad solution envelope of the other
ensembles indicates the more likely scenario is for a low pressure
moving through New England Thursday, with modest warm air aloft
(TROWAL) pivoting behind this low coincident with weak deformation
atop an inverted trough supporting heavier snow generally from
Lake Erie through northern New England. This robust ascent may
overlap effectively with a deepening DGZ as well, with the cold
column supporting fluffy SLR that can accumulate rapidly. While
confidence remains lower than usual at this time range, current WPC probabilities are moderate to high (50-90%) for at least 4" of
snow in the vicinity of Lake Ontario and northeast into the St.
Lawrence Valley and parts of the Adirondacks.

Farther southwest, there is higher confidence in brief but
impressive upslope snow behind the arctic front on Thursday.
Forecast soundings indicate a deepening PBL with theta-e lapse
rates around 0C/km, coincident with impressive ascent into the DGZ
and then lifting into the terrain, especially from the Laurel
Highlands south into the Southern Appalachians. Initially some of
this precipitation may be rain, but will quickly dynamically cool
(and thermally cool behind the front) leading to periods of heavy
snowfall beginning early Thursday and persisting through much of
D3. WPC probabilities have dropped a bit as QPF trends have been
more to the north, but still indicate a 30-50% chance for at least
4" of snow across the higher terrain of WV, with high probabilities

70% or more) for 2+ inches along most of the Appalachians from SW

NC through the Laurel Highlands of PA.


Weiss


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FOUS11 KWBC 130808
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
308 AM EST Tue Jan 13 2026

Valid 12Z Tue Jan 13 2026 - 12Z Fri Jan 16 2026


...Great Lakes...
Days 1-3...

After a day of light snow across the Upper Great Lakes today thanks
to a Canadian clipper racing east across southern Ontario, a more
potent 500mb shortwave trough with an accompanying arctic cold
front will reinvigorate the lake-effect snow machine starting
tonight. Robust CAA in wake of the arctic front will result
numerous multi-banded streamers, especially over the northern half
of the U.P., northern and western L.P., and south of Lake
Michigan. Additional LES bands are likely over northeast Ohio, the
Chautauqua Ridge, and as far north as the Tug Hill late Wednesday
and through Thursday. The heaviest totals will be found over
northwest IN and far southwest MI where there is high confidence in
a potent single-band of LES that is likely to generate 1-2"/hr
snowfall rates. WPC probabilities show moderate-to-high chances
(50-70%) for snowfall totals >6" in northwest IN with lower chances
(10-30%) for amounts exceeding 8". Given the intense mesoscale
forcing at play, seeing some localized amounts approaching 12"
cannot be ruled out. WPC's WSSI does depict Moderate Impact
potential in the hardest hit areas of northwest IN which could
result in delays and/or closures along I-94 and I-80.

Elsewhere, WPC probabilities show high chances (>70%) for over 4"
of snow across much of the U.P., while western MI (including
Traverse City) show moderate chances (>50%) for over 4 of snowfall.
For Wednesday and through Thursday, moderate-to-high chances
(50-70%) for snowfall >4" are depicted over northeast OH, the
Chautauqua Ridge, and the Tug Hull Plateau. Some areas along the
Chautauqua Ridge and Tug Hill could top 8" and localized amounts
approaching 12" are possible.


...Central Appalachians through the Northeast...
Days 2-3...

Over the past 12-24 hours, guidance has continued to trend farther
north with the track of the 500mb low traversing southern Ontario
Thursday AM that then heads into Upstate NY Thursday evening. The
mean 250-500mb mean trough axis is also becoming increasingly more
positive, which is resulting in less deepening of the developing
over Upstate NY by Thursday morning. With these trends, the best
divergence and moisture aloft will reside to the north of the 500mb
low over western and far northern NY. Guidance still disagrees as
to the duration and intensity of the snowfall, but the setup still
favors the development of a TROWAL over the region. Snow will
envelop the Adirondacks and North Country that could reach as far
south as the Finger Lakes. Snow is expected across much of northern
New England Thursday morning, but it is worth noting there is
evidence of a 700-300mb dry slot quickly advancing in from the
southwest that could try to end snowfall sooner over the
Adirondacks, Hudson and Champlain Valleys, and into the Green and
White Mountains. The one area that could still see wrap around
snow is western NY and the Chautauqua Ridge where the pivoting
TROWAL and lake enhanced snow bands are likely to linger through
the remainder of Thursday. Snow is also expected to the north of
the 500mb vort max over northern Maine before tapering off Friday
morning.

WPC 24-hour probabilities show the NY's shores along Lake Ontario
and NY's North Country as having moderate chances (40-60%) for
snowfall totals >6" through Thursday night with the Tug Hill
Plateau sporting low chances (10-30%) for localized snowfall totals
approaching a foot. The peaks of the Green and White Mountains are
also likely to see over 6" of snow while northern Maine shows low-
to-moderate chances (30-50%) for snowfall totals >4".

Farther south, guidance has also gradually trended less snowy in
the central and southern Appalachians. Persistent upslope low
amidst cyclonic flow that taps into Great Lakes moisture is likely
to produce anywhere from 1-4" of snow from the Laurel Highlands on
south through the Potomac Highlands and into the Blue Ridge and
Smokey Mountains of TN/NC. The >3,000ft mountain ranges in eastern
WV and the peaks of the Smokeys shows moderate chances (40-60%) for
localized snowfall totals >4" through Thursday afternoon. Snowfall
will taper off by Thursday evening as high pressure over the South
builds in over the region Thursday night.


...Upper Midwest & Northern Plains...
Day 3...

On Thursday, another Canadian clipper system ushers in another
round of snow over northern MN, northern WI, and the western U.P..
A plume of moisture associated with a ribbon of 850-700mb FGEN will
produce some minor snowfall accumulations Thursday afternoon. As
the snow via WAA moves into the U.P. Thursday night, another arctic
front will race south through the Northern Plains. The strong CAA
and steepening lapse rates may trigger snow squalls over the
Dakotas and as far west as eastern MT. WPC probabilities
favor northern MN and northwest WI for low-to-moderate chances
(30-50%) for snowfall totals >4", although a coating to 1" due to
passing snow squalls in the Northern Plains are also possible,
along with strong wind gusts that could result in whiteout
conditions locally Thursday night and early Friday morning.


Mullinax




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FOUS11 KWBC 132020
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
320 PM EST Tue Jan 13 2026

Valid 00Z Wed Jan 14 2026 - 00Z Sat Jan 17 2026


...Northern Plains through the Northeast, and the Appalachians...
Days 1-3...

A trough across the eastern CONUS will amplify impressively and
periodically re-load through the period as repeated shortwaves
intensify and drop southeast from Canada. The core of this trough
will deepen most impressively to reach the Gulf Coast Thursday aftn
(NAEFS 500mb heights below the 1st percentile within the CFSR
climatology), but remain below the 10th percentile with secondary
amplification occurring on Friday.

Within this trough, and really the driving factor behind amplifying
this trough, will be repeating shortwaves digging out of Canada and
racing southeast through the flow. The first of these will move
from Minnesota to the Ohio Valley D1, with a secondary piece
approaching the Gulf Coast, with both of these impulses rotating
eastward during D2, producing the most intense troughing on
Thursday. Within this progressive flow, even as these lead impulses
rotate away on Friday, the next vorticity lobe will follow
immediately in its wake, moving from the Northern Plains to the
Mid-Mississippi Valley on D3.

This pattern will produce multiple days of lake effect snow (LES)
downwind of the Great Lakes, especially in the more northerly belts
as winds become NNW beneath strong CAA. 3-day WPC probabilities for
LES are high (>70%) for more than 8 inches in the higher elevations
of the U.P. including the Huron and Porcupine Mountains, as well as
along the E/SE shore of Lake Michigan into northern Indiana, and
across the Tug Hill Plateau, with lower but still significant
probabilities (30-50%) for 8+ inches along the Chautauqua Ridge.
The heaviest LES is likely in a single band off Lake Michigan into
SW MI/NW IN late Wednesday through late Thursday.

Across the Central Appalachians and Northeast, the lead shortwave
will not only work together with an Atlantic-offshore jet streak to
create low pressure development across the Northeast, but also drag
an arctic front from the Ohio Valley through the Mid-Atlantic on
Thursday. This will create a short period of heavy upslope snow
from the higher elevations of NC through the Laurel Highlands of PA
where WPC probabilities are moderate (50-70%) for at least 4
inches, generally above 3000 ft, with locally 6-8 inches possible.
Farther north into Upstate NY and northern New England, a weak
TROWAL may pivot westward north of the surface low and combine with
an inverted surface trough to enhance snowfall D2. Trends in the
guidance continue to shift the heaviest snowfall north into Canada,
but a narrow corridor of heavy snow is likely, reflected by WPC
probabilities for 6+ inches that are 50-70% from eastern Lake
Ontario (where some lake enhancement is likely) through the St.
Lawrence Valley and the Adirondacks.

Finally, on D3 with the next shortwave digging out of Saskatchewan
into the Upper Midwest, height falls and modest warm/moist
advection will create a swath of generally light snow, followed by
strong winds behind yet another arctic front. WPC probabilities
indicate only a 10-30% chance for at least 4 inches of snow for
parts of SD/MN/WI, but WSSI-P suggests an increasing threat for
blowing snow impacts just behind this wave, so travelers should be
prepared for hazardous driving Friday despite the modest snowfall
amounts forecast.


Weiss


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FOUS11 KWBC 140751
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
251 AM EST Wed Jan 14 2026

Valid 12Z Wed Jan 14 2026 - 12Z Sat Jan 17 2026


...Northern Plains through the Northeast, and the Appalachians...
Days 1-3...

A longwave trough across the eastern CONUS will amplify and
periodically re-load through the upcoming weekend as repeated
shortwaves intensify and drop southeast from Canada. The core of
this trough will deepen most impressively over the Gulf Coast
Thursday aftn (ECMWF 500mb heights as low as the 0.5 climatological percentile). Within this progressive flow, even as these lead
impulses rotate away on Friday, the next shortwave trough will
follow immediately in its wake, moving from the Northern Plains to
the Mid-Mississippi Valley Friday night. Similar to the Southeast
on Thursday afternoon, 500mb heights over the Missouri River Valley
are likely to be as low as the 0.5 climatological percentile.

The headlining weather hazard, aside from some of the coldest
temperatures and wind chills of the season-to-date, will be the
multiple days of lake effect snow (LES) downwind of the Great
Lakes, especially in the more northerly belts as winds become NNW
beneath strong CAA. WPC probabilities for LES are high (>70%) for
more than 8 inches in the higher elevations of the U.P. including
the Huron and Porcupine Mountains, as well as along the E/SE shore
of Lake Michigan into northern Indiana. Lake-enhanced snowfall
will also unfold along the Chautauqua Ridge and Tug Hill through
Thursday. There are likely to be some localized totals over 12
inches along the Chautauqua Ridge, along the shores of Lake
Ontario, and on the Tug Hill. The heaviest LES is likely in a
single band off Lake Michigan into SW MI/NW IN late Wednesday
through late Thursday. CAMs guidance is showing steep lapse rates
and exceptional vertical velocities that coincide within a fully
saturated DGZ-- a clear sign of a robust LES band. WPC
probabilities show moderate chances (40-60%) for snowfall totals

12 inches where localized amounts approaching 20" cannot be ruled

out given the potential for prolific >2"/hr snowfall rates beneath
a band that will oscillate between southwest MI and northwest IN
for a 12-24 hour stretch.

Across the Central Appalachians and Northeast, the lead shortwave
will not only work together with an Atlantic-offshore jet streak to
create low pressure development across the Northeast, but also drag
an arctic front from the Ohio Valley through the Mid-Atlantic on
Thursday. This will create a short period of heavy upslope snow
from the higher elevations of NC through the Laurel Highlands of PA
where WPC probabilities are moderate (50-70%) for at least 4
inches, generally above 3000 ft, with locally 6-8 inches possible.
The tallest peaks of the Smokey Mountains could see localized
totals approach 12 inches. Farther north into Upstate NY and
northern New England, model guidance has trended snowier over the
past 12-24 hours of model cycles as the slightly longer duration
of moderate-to-heavy snowfall just north and west of the 850mb low
appears to be coming to fruition. The deformation zone will
maintain a saturated profile long enough, within an atmosphere that
supports rising SLRs, to produce heavy snowfall beginning as early
as Wednesday afternoon and continuing into Thursday. WPC
probabilities show moderate-to-high chances (50-70%) for snowfall
totals >8 inches from northwest PA through much of western NY and
into NY's North Country and St. Lawrence Valley.

Finally, on D3 with the next shortwave digging out of Saskatchewan
into the Upper Midwest, height falls and modest warm/moist
advection will create a swath of generally light snow, followed by
strong winds behind yet another arctic front. WPC probabilities
indicate only a 10-30% chance for at least 4 inches of snow for
parts of SD/MN/WI, but WSSI-P suggests an increasing threat for
blowing snow impacts just behind this wave, so travelers should be
prepared for hazardous driving Friday despite the modest snowfall
amounts forecast. Farther east, the shortwave trough will once
again kick-up LES bands across the U.P. and western shores of
Michigan. WPC probabilities show high chances (>70%) for snowfall
totals >4 inches in the U.P.'s Porcupine Mountains and moderate
chances (40-60%) for >4 inches of snow over the western MI shore.
The Porcupines have the best odds at locally heavy totals with
low-to-moderate chances of totals >8 inches.


The probability for significant ice across the CONUS is less than
10%.


Mullinax/Weiss





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FOUS11 KWBC 141935
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
235 PM EST Wed Jan 14 2026

Valid 00Z Thu Jan 15 2026 - 00Z Sun Jan 18 2026


...Upper Midwest through Northeast, and the Appalachians...
Days 1-3...

The longwave trough in place across the eastern CONUS will
repeatedly reload into the weekend, becoming increasingly amplified
as shortwaves periodically drop south out of Canada and rotate
through the trough and then off the east coast. The core of this
trough will deepen most impressively over the Gulf Coast Thursday
aftn (ECMWF 500mb heights as low as the 0.5 climatological
percentile). Within this progressive flow, even as these lead
impulses rotate away on Friday, the next shortwave trough will
follow immediately in its wake, moving from the Northern Plains to
the Mid-Mississippi Valley Friday night. Similar to the Southeast
on Thursday afternoon, 500mb heights over the Missouri River Valley
are likely to be as low as the 0.5 climatological percentile.

In addition to producing true winter cold air across much of the
eastern 1/3 of the CONUS, and potentially some of the coldest wind
chills of the season, widespread snow is likely from the Upper
Midwest through the Tennessee Valley and back northeast through the
Central Appalachians and into the Northeast. While most of this
snow will be more "conversational" and light than impactful, there
are a few areas that will experience more significant snowfall.

Great Lakes: Periods of lake effect snow (LES) are likely each day
as persistent cyclonic flow and periodic shortwaves/fronts renew
CAA across the lakes. The heaviest LES is likely D1, especially
downwind of Lake Michigan into northern Indiana where, despite some
modest longitudinal fluctuations in the axis from the most recent
model runs, a long fetch north-south across Lake Michigan should
result in a narrow and intense single band of snow into far SW MI
and northern IN. Here, HREF probabilities for 1+"/hr snowfall peaks
above 60% for much of D1, and with locally 2-3"/hr snowfall rates
possible, WPC probabilities support a high risk (>70%) for more
than 12", and locally up to 20 inches is possible. Elsewhere, heavy
snowfall is likely south of Lake Erie along the Chautauqua Ridge
where WPC probabilities indicate a moderate risk (30-50%) for more
than 12 inches. Otherwise, while LES will be periodic and briefly
intense at times all 3 days, additional snowfall in other areas
should generally be around 6 inches or less, especially southeast
of Lake Ontario and across portions of the U.P. of MI.

Central Appalachians: The passage of an arctic front associated
with the lead shortwave will quickly cool the column to change
precipitation from rain to snow, with post-frontal gusty westerly
winds leading to pronounced upslope flow. Regional soundings
suggest favorable ascent into steepening lapse rates and elevated
low-level moisture to support heavy snow rates from the higher
elevations of NC near the Smoky Mountains northward through the
Central Appalachians of WV and into the Laurel Highlands. Guidance
has trended a little wetter and more intense with this event, and
WPC probabilities now reflect a high chance (>70%) for more than 6
inches in the higher terrain, generally above 3000 ft, across this
region on D1. Light snow showers will likely continue, although
with minimal additional accumulations on D2, but renewed upslope
flow with a secondary front D3 could again result in a few inches
of snow (WPC probabilities above 30% for 4+ inches) across the
higher elevations from NC to WV once again.

Interior Northeast: A surface low pressure moving across PA tonight
will continue to push northeast, reaching Atlantic Canada by
Friday morning. This low will be accompanied by modest warm/moist
advection to spread precipitation across Upstate New York and
northern New England. While the guidance has trended north to focus
the heaviest snowfall across Canada, a modest TROWAL pivoting
westward behind this low and interacting with an inverted surface
trough elongated from the primary low will pivot some heavier
snowfall tonight through Thursday aftn. Brief snowfall rates in
excess of 1"/hr are possible (10-30%) across the Adirondacks,
northern VT, and near Lake Ontario tonight before lifting northeast
through Thursday. As the low pulls away, some upslope snow on
increasing NW winds may also lead to heavier rates across the
Adirondacks and Greens. WPC probabilities across this area are
moderate (30-70%) for 8+ inches of snow through Friday, with the
greatest accumulations likely near the St. Lawrence Valley, the
Adirondacks, and the northern Greens.


...Northern/Central Plains...
Day 2...

A potent shortwave and accompanying vorticity lobe will drop
rapidly southward out of Saskatchewan/Manitoba into the Dakotas and
then continue to dig southeast reaching the Mid-Mississippi Valley
by 00Z Saturday /end of D2/. This feature will drive an arctic cold
front southward, and the overlap of modest, but transient, height
falls, PVA, and low-level convergence along the front will
manifest as periods of snow showers, with coverage and snowfall
amounts limited by below-normal PWs and ongoing CAA. However,
impressively strong winds within the PBL and exceptionally steep
low-level lapse rates will encourage any snow showers to be
accompanied by gusty winds, and where low-level fgen combines with
modest 0-2km CAPE of 100-200 J/kg, convective snow showers may
result. While the duration and coverage of these may be limited, as
reflected by most simulated reflectivity, any of these snow
showers will likely include limited visibility and brief heavy snow
rates. This could produce hazardous travel as reflected by 30-50%
chance for moderate impacts from the WSSI-P despite snowfall
amounts that will likely (>70% chance) be less than 2 inches from
the Dakotas into western Minnesota and down into Nebraska/Iowa.


The probability for significant ice across the CONUS is less than
10%.


Weiss


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FOUS11 KWBC 150823
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
323 AM EST Thu Jan 15 2026

Valid 12Z Thu Jan 15 2026 - 12Z Sun Jan 18 2026


...Northeast...
Day 1...

Accumulating snowfall will be ongoing this morning across western
and northern NY into northern New England. Additional accumulations
after 12z will be highest across western NY (where some lake
enhancement will occur) and over northern ME...with the probability
of 4"+ of additional snow over 70%. This area of snow will wind
down tonight, although some lingering lake effect snow will
continue along with some wrap around snow into northern ME.


...Central and Northern Plains into the Great Lakes...
Days 1-3...

A mid level trough with multiple lobes of embedded vorticity will
drop into the Northern Plains and Great lakes today into Friday
bringing periods of snow. One area of snow will move into MN, WI
and the Great Lakes ahead of and associated with a low moving out
of Canada today into Saturday. Mainly looking at light snowfall
accumulations with this low, although some heavier totals can be
expected off of Lake Superior and Lake Michigan. Overall this is
setting up to be a long duration of light to moderate snowfall
across these lake effect areas, with 72hr probabilities of
exceeding 8" of snow in the 70-90% range across portions of the
western U.P of MI into northeast WI...and 50-70% over western MI.
Lighter amounts, generally in the 1-4" range, can be expected over
MN into WI.

Snow showers will also accompany this system farther west across
the Dakotas into NE, both along the southward dropping cold front
and in its wake. Snowfall amounts are not expected to be
significant, generally on the order of 1-2" or less...however this
snow will be accompanied by significant wind gusts, likely
resulting in reduced visibility and hazardous travel. These snow
showers should start in ND by Thursday evening, spreading south
into SD Thursday night, and then continuing over much of the
Northern Plains through the day Friday. HREF EAS probabilities of
.01" can be a decent proxy for snow shower coverage...and these
values increase into the 70-100% range Thursday night over much of
ND into eastern SD, dropping closer to 40-60% during the day
Friday. Thus anticipating numerous to widespread coverage of snow
showers as the cold front pushes across Thursday night, decreasing
to scattered coverage during the day Friday. Heavier snow shower
coverage may be more isolated to scattered in nature...but where
these brief heavier rates occur a sharp reduction in visibility can
be expected with wind gusts as high as 40-60 MPH. This setup would
seemingly support at least some snow squall potential near and
just behind the cold front as it drops south Thursday night. Snow
shower coverage and intensity should generally be on a downward
trend Friday, however wind gusts will remain high. One limiting
factor for blowing snow impacts from this system is the lack of
antecedent snow cover...however if we are able to get snowfall
accumulations ~2" Thursday night into early Friday then blowing
snow concerns could increase during the day Friday, especially
within snow showers.


...Ohio Valley, Southeast, Mid-Atlantic and Northeast...
Days 2-3

A decent amount of uncertainty exists Friday night into Sunday from
the OH Valley into the East Coast...all related to how the multiple
vort maxes interact within the large scale trough moving towards
the East Coast. Model guidance is trending a bit stronger with one
lobe of vorticity Friday night into Saturday moving from the OH
valley into the Mid-Atlantic. This should support an expanding area
of light to moderate precipitation across TN/KY Friday night,
spreading into the Mid-Atlantic and Northeast on Saturday. Not
anticipating any significant snowfall from this feature, but some
light snow accumulations are possible over portions of northeast TN
into KY Friday night. Temperatures are marginal, but enough of the
guidance is just cold enough to support the potential for 1-2" of snowfall...and the latest WPC probabilities of 1"+ are in the
30-60% range, which seem reasonable. Some light snow (generally
under 1") could then spread into portions of the northern Mid-
Atlantic saturday morning, with totals upwards of 1-3" possible
across the interior Northeast.

Attention will then turn to energy diving into the base of the
large scale trough and how this evolves from the Gulf Coast to the
East Coast. Seemingly have 3 deterministic model camps with this
system. The 00z GFS is the slowest and most aggressive with this
feature, taking it neutral to negatively tilted by 12z Sunday
resulting in a more expansive swath of precipitation over the
Southeast Saturday night into Sunday morning. While boundary layer
temperatures are marginal, some accumulating snowfall would be
possible over the Southeast states in this scenario. On the other
hand the ECMWF, while slower like the GFS, is more positively
tilted, keeping the system more suppressed, and thus little to no
winter precip through 12z Sunday. The 00z AIGFS/AIFS/GEM all depict
a quicker shortwave trough that results in a precipitation axis
farther east than the GFS, but moving quicker up the East Coast as
well. This scenario is a warmer one however, with the bulk of the
precipitation staying ahead of the colder airmass. Thus most of the
precip over the Southeast in this scenario is rain through 12z
Sunday. Not really seeing any clear trend to support hedging one
way or another with the forecast at this point, so will just need
to continue to monitor and hope for a more consistent trend today.
Current probabilities of 1"+ of snow through 12z Sunday are low,
only peaking around 5-10% over portions of AL and GA. Probabilities
do increase into the 20-30% range from NC into New England later
Sunday, but the aforementioned model spread will play a significant
role in how that forecast plays out.

Chenard



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FOUS11 KWBC 152046
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
346 PM EST Thu Jan 15 2026

Valid 00Z Fri Jan 16 2026 - 00Z Mon Jan 19 2026

...Central and Northern Plains into the Great Lakes...
Days 1-3...

Persistent longwave trough across the eastern CONUS will=20
repeatedly re-load through the weekend in response to multiple=20
embedded shortwave troughs and accompanying vorticity lobes=20
swinging through.=20

The first of these will be exiting the Northeast into
Atlantic Canada D1 as a closed low with the accompanying trough
axis extending into the Southeast. Behind this trough and the
accompanying cold front, strong CAA in its wake will drive
continued lake effect snow (LES), especially east of Lakes Erie=20
and Ontario before shortwave ridging develops Friday aftn shutting
off the LES. WPC probabilities D1 are modest for 4+ inches of
additional snow, highest southeast of Lake Ontario where it reaches
30-50%.

Immediately in the wake of this first impulse, a second shortwave
will dig out of Saskatchewan and race S/SE, reaching the Mid-
Mississippi Valley by D2 before continuing to rotate E/NE into New
England on Sunday. This shortwave will push a power arctic cold
front southward beneath it, and a clipper-type low is also expected
to track to the southeast across the Great Lakes during this time.
While the accompanying synoptic snow through WAA is likely to be
minimal, renewed CAA across the Lakes should result in additional
LES, with more widespread coverage as cold N/NW flow envelops the
entire region. A third shortwave is expected to cross into the
Great Lakes on Sunday with subsequent ascent and moisture leading=20
to more snowfall, but additional accumulations before 00Z Monday
should be minor. Before that time, however, 3-day snowfall
probabilities from WPC indicate a high risk (>70% chance) for at=20
least 8 inches across the western U.P. and much of the western=20
shore of the L.P. where locally 1-2 feet is possible. Lesser=20
amounts are expected east of Lake Ontario, but still modest=20
accumulations exceeding 8 inches have a low chance (10-30%) of=20
occurring.

In addition to the LES, the arctic cold front and post-frontal CAA
will provide sufficient ascent for widespread snow showers and
possible snow squalls across the Northern Plains, Upper Midwest,
and potentially into parts of the Great Lakes/Ohio Valley. This
will begin tonight across the Dakotas, and then persist through
Friday night while expanding southeast. While the setup does not
appear extremely favorable for strong snow squalls, linear bands
aligned perpendicular to the front within a region of elevated
0-2km fgen, increasing low-level moisture, and steepening lapse
rates where winds at the top of the PBL exceed 50 kts in some
areas, will support widespread snow showers (or squalls) with brief
heavy snow rates and gusty winds. While snowfall accumulations
across this region accompanying these squalls will be minimal, when
snow occurs it will fall heavily, and when combined with the strong
winds will create periodic near zero visibility and dangerous
driving. The alignment of these snow showers/squalls will also
support multiple rounds in some areas through D2.

Key Messages have been issued for these snow squalls, and they are
linked at the bottom of this discussion.


...Ohio Valley, Mid-Atlantic, and Northeast...=20
Days 1-3...

Progressive flow within a reloading and persistent mid-level
longwave trough will create active winter weather across the area
through the weekend.

For D1, a low pressure system rapidly exiting into Atlantic Canada
will leave residual moisture and ascent across primarily Maine
where a theta-e ridge continues to pivot briefly tonight, with
increasing NW flow/upslope ascent occurring as the low pulls away.
Forecast soundings indicate a rapid drying of the DGZ tonight so
any moderate snow should wane quickly by Friday morning, but WPC
probabilities indicate a low risk (10-30%) for an additional 4+
inches of snow in northern ME.

Thereafter, the mid-level trough begins to re-amplify in response
to a shortwave diving through the Great Lakes and elongating into
the Ohio Valley and Central Plains. This evolution will drive an
arctic cold front sharply east, reaching the Mid-Atlantic states by
the end of D2 /00Z Sunday/. A shortwave downstream of this front
may help develop a wave of low pressure which will bring some light
to moderate snowfall to New England, although WPC probabilities for
more than 2" of snow D2 are only around 30%, highest in the higher
elevations of the Catskills and Berkshires. More substantial
snowfall is likely through lift along the front, followed by
impressive upslope snow into the Central Appalachians, as well as
parts of western PA. Steepening lapse rates will keep the DGZ
relatively shallow, but sufficient ascent into the moistened column
will result in periods of moderate to heavy snowfall which may
accumulate to more than 4 inches in parts of WV and PA as reflected
by WPC probabilities reaching 30-50%.

Then during D3 /00Z Sunday to 00Z Monday/ an elongated lobe of
vorticity will swing into New England, while a secondary and
sharpening shortwave dives into the primary longwave trough across
the Mississippi Valley. While the lead impulse may cause some light
snow across Maine (WPC probabilities for 4+ inches 10-30%), the
more challenging and bigger concern will be what happens with
moisture spreading northward from the Southeast the latter half of
D3. While uncertainty is significant, there is at least modest
confidence that light precipitation will spread far enough
northwest to bring snowfall to parts of the Mid-Atlantic coast from
eastern VA through coastal NJ, and potentially onto Long Island and
Cape Cod. Current WPC probabilities are modest (30-50% for 1"), but
trends will need to be monitored as the system develops in the next
few days.


...Southeast...
Day 3...

A complex forecast scenario is evolving for portions of the
Southeast beginning around 00Z Sunday and persisting through D3. An
arctic cold front will push into the area Saturday and then=20
progress rapidly to the Atlantic Coast by Sunday morning. As this
front pushes east, a sharpening upper shortwave trough will rotate
near the Gulf Coast, potentially taking on a negative tilt late in
the forecast period (although there is a lot of uncertainty into
the amplitude of this feature). At the same time, a downstream jet
streak will amplify to become powerful over the Mid-Atlantic and
Northeast, leading to weak surface cyclogenesis along the Gulf
Coast. As this wave develops, moisture will spread northward, and
while the column will initially be too warm for wintry
precipitation, rapid cooling behind the front will allow for a
changeover from rain to snow.=20

The speed at which this occurs, as well as how much moisture can=20
remain in the column after transition, will play the most important
role into any possible snowfall accumulations. The GFS continues=20
to be the most robust with the transition and available moisture=20
for snow, while the EC and CMC are weaker and drier. Evaluation of=20
the D3 clusters suggests that both the CMC and GFS ensembles are=20 under-dispersive (with the CMC members nearly uniformly deeper=20
with the trough, while the GFS members are nearly uniformly faster=20
at 500mb), suggesting the EC members and their variety of=20
solutions results in a more accurate solutions via the ECENS mean.
While there is still a lot of uncertainty, confidence is increasing
for at least mixed rain/snow from the Florida Panhandle northeast
through southeast Virginia. While the threat for significant
accumulations appears small, and WSE plumes only have a handful of
members producing >1" of snow, the WPC probabilities have increased
and suggest a 10-30% chance for 1" of snow from southern AL through
the NC Piedmont and into the coastal Mid-Atlantic states. Forecast
changes are almost certain, so those potentially impacted should
remain apprised of the latest forecast through the next few days.


Weiss


...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!6RNjUAou4g17Px_u1pNFlRzORKhcuzmoTm4odAbI2R7Ol= g8xKox0NZQc9EVJ7SQwiAS7NX09bAHxt-zgZW50whtt9wE$=20



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FOUS11 KWBC 160911
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
411 AM EST Fri Jan 16 2026

Valid 12Z Fri Jan 16 2026 - 12Z Mon Jan 19 2026

...Central and Northern Plains into the Midwest...=20
Days 1 and 3...

Longwave trough re-establishes over the Great Lakes today where it
persists into next week as multiple shortwave troughs swing
through.

An arctic cold front currently pushing across ND will push
south-southeast into the Midwest today. Strong frontal CAA will=20
continue to provide sufficient ascent for widespread snow showers=20
and likely additional snow squalls both along the front as it=20
moves across the rest of the north-central Plains through the
Missouri River Valley today and potentially IL/IN this evening.=20
Potent snow streamers in cloud streets/horizontal convective rolls=20
in the NW flow behind the front should also trigger snow squall
warnings particularly over SD/Neb this morning through midday.=20=20
Some particulars on the linear bands include alignment=20
parallel to the flow within a region of elevated 0-2km fgen,=20
increasing low- level moisture, and steepening lapse rates where=20
winds at the top of the PBL exceed 50 kt. Snowfall in these
potentially lingering/repeating banding could become locally heavy=20
and when combined with the strong winds will create near zero=20
visibility and dangerous driving.=20

Key Messages are being updated for these snow squalls with the link=20
at the bottom of this discussion.


...Great Lakes...
Days 1-3...

The potent wave with the Arctic front has a leading cold front
currently over IA/KS which will swing east to the Appalachians
tonight and off the Eastern Seaboard Saturday with the Arctic
front quickly on its heels. The next reinforcing shortwave trough
then crosses the Great Lakes Sunday/Sunday night.=20
Renewed CAA across the Great Lakes today will reinstate LES with=20
more widespread coverage in snow belts as cold N/NW flow envelops=20
the entire region. Day 1 PWPF for >6" is 30-50% over the western
U.P., and the western L.P. This shifts to the Tug Hill and across
southern VT/NH for Day 1.5. Then Days 2 and 3 are highlighting
again over the western U.P. and western L.P.


...Ohio Valley, Appalachians, and Northeastern Seaboard... Days=20
1-3...

Progressive flow within a reloading and persistent mid-level
longwave trough will create active winter weather across the area
through the weekend.

The arctic cold front reaches the Ohio Valley late tonight and the
Mid- Atlantic states Saturday. Snowfall is likely through lift=20
along the front, followed by impressive upslope snow for the=20
Central and Southern Appalachians. Steepening lapse rates will=20
keep the DGZ relatively shallow, but sufficient ascent into the=20
moistened column will result in periods of moderate to heavy=20
snowfall with Day 1.5 PWPF for >4" spotty for 20-40% probs from
western PA through WV and the higher Apps along the TN/NC border.

Sunday and Sunday night an elongated lobe of vorticity will swing=20
into New England, while a secondary and sharpening shortwave dives=20
into the primary longwave trough across the Mississippi Valley.=20
While the lead impulse should bring snow to northern Maine (WPC Day
2 probabilities for 4+ inches 10-30%), the more challenging and=20
bigger concern will be what happens with moisture spreading=20
northward from the Southeast and along the Mid-Atlantic Coast=20
starting late Saturday night. Confidence is growing for light to
moderate snow from eastern VA through coastal NJ, Long Island, and
southern New England where Day 2.5 probs for >2" are 20-80%=20
(highest in on the central Jersey Shore. The low track is offshore,
so this is the backside precip.


...Southeast...
Days 2/3...

A baroclinic leaf develops downstream of the digging, positively
tilted trough axis over the Mid-South Saturday night with strong
cold air advection and snow potential for the Southeast
Piedmont through the shortwave trough passage Sunday evening. This
is the southern extent of the more notable snow mentioned above for
the Mid-Atlantic. Day 2.5 snow probs for >1" are around 40% in
Southeast VA with some 20% reaching into central NC. While most
guidance has low to no snow, there are notable outliers like the
06Z NAM with decent snow from central GA through central NC. This
will continue to be monitored as the system gets into the CAMs
today.


Jackson



...Winter Storm Key Messages are in effect and linked below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!5nz7zLo_-HKjp4ztUZSBDzH0Pt66De4raR4tqx5cnhKfQ= 4qGdTeZ-Djv7G_j9Nm6i4uqmWZChgeiXy02GdB7imda5mE$=20



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FOUS11 KWBC 161925
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
225 PM EST Fri Jan 16 2026

Valid 00Z Sat Jan 17 2026 - 00Z Tue Jan 20 2026

...Central and Northern Plains into the Midwest...=20
Days 1 and 3...

With a longwave trough and embedded shortwaves forecast to persist
the next few days, bouts of snow will continue for the Plains to
the Great Lakes/Midwest. Snow squalls along the Arctic front will
yield generally low amounts of snow but potentially
hazardous/dangerous driving conditions. Snow showers and squalls=20
this afternoon will shift southward/eastward tonight through the
Midwest with less coverage. Another shortwave from Canada will
carry another threat for some banded snow showers and some snow=20
squalls Sunday over the Northern Plains to the Upper Midwest/Corn=20
Belt. Snowfall in these potentially lingering/repeating banding=20
could become locally heavy for a time and when combined with the=20
strong winds will create near-zero visibility.=20

Key Messages for these snow squalls are linked at the bottom of=20
this discussion.


...Great Lakes...
Days 1-3...

Persistent cyclonic flow around the Great Lakes will favor rounds=20
of lake effect snow downwind of all Great Lakes Lead system tonight
will favor Michigan (esp. the U.P.) as the surface low moves into=20
Ontario. Next system on Sunday will renew the lake machine across=20
Michigan then into the NY lake belts as the next area of low=20
pressure moves right across Lake Superior into Ontario. WSW flow=20
over Lakes Erie/Ontario could move the bands quite far north (e.g.,
north of BUF and ART) but the progressive flow would vary the band
locations through the period. Three-day snow totals will be=20
modest, with the favored areas (northern shore of the U.P., western
Lower Michigan, and into the Tug Hill) show >50% probabilities for
at least 12 inches of snow.=20


...Ohio Valley, Appalachians, and the Northeast...
Day 1...

Shortwave and cold front out of the Midwest will move into the
Appalachians with generally light to locally modest snow, enhanced=20
over the terrain (western PA/MD and eastern WV) tonight. WPC
probabilities for at least 4 inches of snow are about 20-50%.=20

A strengthening upper jet will move into the Northeast early
Saturday with modest snowfall expanding through the interior
Northeast, especially over the Berkshires and into the southern
Green Mountains just ahead of the cold front. Snow could exceed
1"/hr in areas of the Poconos and northwestern NJ through parts of
the Catskills and into western MA per the 12Z HREF (30-60%=20
chance). The front should clear eastern Maine after 00Z and largely
end most accumulation. WPC probabilities for at least 6 inches of=20
snow are >50% over northwestern MA into southern VT as well as into
the Tug Hill Plateau.


...Southeast, Mid-Atlantic, Northeast...
Days 2-3...

Within the active pattern in the East is a southern portion of the full-latitude trough that swings through the Lower MS Valley=20
Sunday morning. This will bring colder temperatures to the
Southeast as precipitation is slowly moving through the region
along/behind the front. Models have been struggling with how
quickly to move in colder air as precipitation ends, but some light
snow is possible over GA into the Carolinas Sunday morning of a
dusting to a tenth or two.=20

Further up the coast, precipitation will expand northeastward in
the right rear quad of the >160kt jet atop marginal to cold
temperatures (milder along/east of I-95 in the Mid-
Atlantic). Elongated baroclinic zone and areas of surface low=20
pressure will lift northeastward just off the Mid-
Atlantic/Northeast coast Sunday night. Models have struggled here
with the westward QPF extent and are sensitive to the
timing/strength of upstream/incoming mid-level systems as the flow
remains wide open. For now, have remained fairly steady on the
amounts which should result in a swath of a few inches of snow from
the Mid-Atlantic into the NYC area and New England. Highest
probabilities for at least 4 inches of snow are in eastern Maine

50%) as any chance of a more organized system is higher as it=20

approaches Nova Scotia. However, a light snow of 1-3" is likely=20
from NJ northeastward along/east of I-95/91 where WPC probabilities
of at least 2 inches are at least 30%.

Fracasso


...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!87Gc6PAfEmAFY1wwwek2esPmSCIZYqVDtFagoGIre7OrO= jq5eIs55aadK1HxyPINNkLRan8wbhzLqIvIYfPQxq8pr0A$=20



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FOUS11 KWBC 170856
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
356 AM EST Sat Jan 17 2026

Valid 12Z Sat Jan 17 2026 - 12Z Tue Jan 20 2026


...Great Lakes...
Days 1-3...

Shortwave trough passages in persistent cyclonic flow through the=20
Great Lakes will favor rounds of lake effect snow for at least the
next week.

A long wave trough over the western Lakes this morning will slowly
shift east through tonight. Northerly flow over Lake Superior will
bring LES to the western U.P. with westerly flow over the L.P.
where Day 1 snow probs for >6" are 40-60% in narrow snow belts.

The next reinforcing trough moves in from the west with NWly flow
bringing more snow to the western U.P. and most of the L.P. western
shore. SWly flow over Lake Erie pushes some single banding into
Buffalo, NY. These areas have Day 2 snow probs for >6" in the
20-60% range. Then the next shortwave trough moves in from the west=20
Monday night with LES until ridging builds briefly late Tuesday.
Day 3 PWPF for >6" is over the eastern U.P. on westerly flow along
with the northern L.P. Most notably however, is single banding in
westerly flow over Lakes Erie and Ontario with Day 3 PWPF for >6"
40-80%.


...Ohio Valley, Appalachians, and the Northeast...
Day 1...

Arctic cold front will shift east from the Midwest this morning and
cross PA this afternoon. Snow squalls could accompany this front
mainly over Ohio and western PA/NY which are highlighted in ongoing
Key Messages that are linked below.=20

A SWly jet stream strengthens in place over the eastern U.S.
through tonight as a very positively-tilted trough shifts down the
Plains and pivots over the Mid-South. Downstream of this trough
will be expanding snow through the interior Northeast, especially=20
over the Poconos, Catskills, Berkshires and southern Green=20
Mountains just ahead of the cold front. Snow could exceed 1"/hr in
these areas per the 00Z HREF. This precip clears eastern Maine=20
this evening. Day 1 WPC probabilities for >4" are 50% in the Mohawk
Valley of NY and over the southern Greens, Whites, and eastern
Maine with 20-30% probs over the Poconos/Catskills, and Berkshires.=20


...Southeast, Mid-Atlantic, Northeast...
Days 2-3...

Within the active pattern in the East is a southern portion of the full-latitude trough that swings through the Lower MS Valley=20
early Sunday. This will bring colder temperatures to the Southeast
as precipitation is slowly moving through the region along/behind=20
the front. Models are in better agreement tonight allowing enough
cold air in before precipitation ends to allow some light snow from
northern FL through the Carolinas Sunday morning with a dusting to
half an inch.=20

Further up the coast, precipitation will expand northeastward in
the right entrance of the >160kt jet atop marginal to cold=20
temperatures (milder along/east of I-95 in the Mid-Atlantic).=20
Elongated baroclinic zone and areas of surface low pressure will=20
lift northeastward just off the Mid-Atlantic/Northeast coast=20
Sunday night. Models have struggled here with the westward QPF=20
extent and are sensitive to the timing/strength of=20
upstream/incoming mid-level systems as the flow remains wide open.=20
For now, have remained fairly steady on the amounts which should=20
result in a swath of a few inches of snow from the Mid-Atlantic=20
into the NYC area and New England. 10 to 20% probs for >4" in Day 2 are
limited to eastern Maine and southeastern New England. The Day 2
swath of >2" over 10% extends south through NJ into the Delmarva.


...Central High Plains...
Days 2/3...

Another Arctic cold front plunges down the Plains tonight through=20
Sunday. This banks cold air over the High Plains/against the front
ranges of the Rockies ahead of a reinforcing shortwave trough that
shifts down the Rockies Sunday night through Monday. Right entrance
jet dynamics over the existing front will allow banded snow to
develop over central MT/WY Sunday night with what appears to be the
main banding early Monday from northern CO terrain through western
KS. The WNWly orientation of these bands is parallel to flow and
should allow for persistence of moderate to locally heavy narrow
bands of snow. As of now Day 2.5 snow probs for >2" are around 20%
along the KS/CO border, but that is likely to increase as the
system gets closer. The ECAIFS was featuring this precip two nights
ago and global physical models are finally catching up. A risk for
4" or more is possible in these persistent banding scenarios.


Jackson



...Winter Storm Key Messages remain in effect and are linked=20
below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!53LqTlmiHMfFGsvloks6bLMMHenjsnI7u8iz2V4YYXMnf= wtJNLrDQZ30xNDPeBw5guoNHsTuPVbwDfbbLJhW__x0xiw$=20



$$

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FOUS11 KWBC 172007
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
307 PM EST Sat Jan 17 2026

Valid 00Z Sun Jan 18 2026 - 00Z Wed Jan 21 2026


...Great Lakes...
Days 1-3...

Shortwave trough passages in persistent cyclonic flow through the=20
Great Lakes will favor rounds of heavy lake effect snow for at=20
least the next week. The Great Lakes are currently mostly ice free
(total ice cover estimated at 15.5% on Jan 16), with surface water
temperatures between 2-6C (warmer over southern Lake Michigan and
Lake Ontario).=20

A long wave trough over Great Lakes tonight will shift east Sunday,
but reinforced by the next trough swinging around the anchored
upper low over the Hudson Bay. For D1, the highest probabilities
(40-70%) for more than 6 inches of snowfall is across the west-
central MI L.P. along the shores of eastern Lake Michigan, where=20
westerly flow and an inverted surface trough are expected to aid in
localized heavy snowfall.

The next reinforcing trough set to bring heavy snowfall during the
D2-D3 period is forecast to move in from the west with NWly flow=20
bringing more snow to the U.P. and most of the L.P. western shore.
Gusty winds up to 40 mph are also expected across the MI U.P,=20
which could lead to additional impacts associated with blowing=20
snow. SWly flow over Lake Erie pushes some single banding into=20
Buffalo, NY on Monday. These areas have Day 2 snow probs for >6"=20
in the 50-80% range. Then the next shortwave trough moves in from=20
the west Monday night with LES until ridging builds briefly late=20
Tuesday into the western Great Lakes. Day 3 PWPF for >6" is over=20
the eastern U.P. Most notably however, is single banding in=20
westerly flow over Lakes Erie and Ontario with Day 3 PWPF for >6"=20
60-90%. For the entire D1-D3 period, probabilities for >12" are
70-90% downwind of Lake Erie and Ontario, including the Buffalo
metro region.


...Southeast, Mid-Atlantic, Northeast...
Days 1-2...

Positively-tilted full-latitude trough this evening will move into
the Mid-South overnight, carrying a surface cold front through the
Southeast. By 12Z Sunday, cold front will be well into the Atlantic
with lagging precipitation over central/southeastern GA just in
advance of the sharp mid-level shortwave. With these cases, even
with surface temperatures just above freezing, dynamic cooling
could easily bring snow to the surface and accumulate via modest
rates 0.5-0.75"/hr per some of the CAM guidance. Though they have
wavered on how things come together, 12z guidance has nudged up
toward supporting a burst of snow over central/southeastern GA
which could accumulate to an inch or so (WPC probabilities of >1"
are around 10% but with upside potential). Light snow from a
dusting to half an inch is possible from the northern FL Panhandle
into upstate SC (>20-30% chance).=20

Further up the coast, precipitation will expand northeastward in=20
the right entrance of the >160kt jet atop marginal to cold=20
temperatures (milder along/east of I-95 in the Mid-Atlantic) and
increasing lower to mid-level FGEN. Elongated baroclinic zone and=20
areas of surface low pressure Sunday morning will coalesce into a
coherent surface low that is forecast to lift northeastward just=20
off the Mid-Atlantic coast to just outside the 40/70 benchmark Sunday
evening. 12Z guidance continued to trend westward with the QPF
axis/edge and have trended up in QPF and thus snow for the
Northeast. This could also keep shoreline temperatures milder for a
time before the low passes by. Snow could fall heavy for a period
over southern/southeastern New England Sunday evening per the 12Z
HREF (20-40% chance of >1"/hr rates). A swath of a few inches of=20
snow is likely from the Mid-Atlantic into the NYC area and New=20
England with upside potential over the terrain (Worcester hills,
etc.). WPC probabilities for at least 4 inches of snow are >50%
over eastern CT through RI and southeastern MA outside the Cape and
Islands. Into Maine, a stripe of a few/several inches of snow is
likely along the coast where probabilities for at least 4 inches of
snow are >40%.=20


...Northern Plains...
Day 1...

**Snow squalls likely across parts of the northern Plains on
Sunday. Key Messages linked at the bottom of the discussion***

The next in a series of arctic cold fronts is forecast to dive
southward across the northern Plains on Sunday, with the greatest
potential for scattered snow squalls along the northern High
Plains. Timing for this front and associated snow squalls/streamers
behind the front starts in eastern MT/western ND during the=20
morning hours and quickly pushes southward into western SD and NE
into the afternoon. Lapse rates per several 12z CAMs near or exceed
6-7C/km for a brief period along the front and SNSQ parameters=20
rise above 4-5 between eastern MT and central NE. These parameters=20
combined with low-to-mid level FGEN intersecting with a healthy=20
100mb wide DGZ should allow for efficient snowfall rates within=20
these showers and bands. Wind gusts up to 60 mph are also possible=20
with this system, adding to the blowing snow potential.

Snow squalls are particularly dangerous for those traveling on
roadways, with extremely low visibilities and slippery conditions
developing rapidly. Be sure to slow down, turn on your lights, and
exit the highway if possible should you get caught in a snow
squall.


...Central High Plains...
Days 2-3...

With cold air banked over the High Plains/against the front ranges
of the Rockies ahead of a reinforcing shortwave trough Sunday=20
night through Monday, conditions will be set for a period of snow
over eastern CO to KS. Right entrance jet dynamics over the=20
existing front will allow banded snow to develop over central MT/WY
Sunday night with what appears to be the main banding early Monday
from northern CO terrain through western KS. The WNWly orientation
of these bands is parallel to the flow and should allow for=20
persistence of moderate to locally heavy narrow bands of snow. As=20
of now WPC probabilities for >2" are 10-20% along the KS/CO=20
border, but that is likely to increase as the system gets closer.=20
QPF trends has been up overall and a risk for 4" or more is=20
possible in these persistent banding scenarios.

Fracasso/Snell/Jackson


...Snow Squall Key Messages are in effect. Please see current Key=20
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!4O44Oh9C5u6tIlCTliLi6mxu8BcIbKtbjpq7987JV_82b= OrTDGEDnOCpz0-LLQBikF8uV75kXdSRrKcBcTI-CQJ3RK0$=20



$$

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FOUS11 KWBC 180904
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
404 AM EST Sun Jan 18 2026

Valid 12Z Sun Jan 18 2026 - 12Z Wed Jan 21 2026


...Great Lakes...
Days 1-3...

Shortwave trough passages around an anchored deep low over Hudson
Bay maintains cyclonic flow through the Great Lakes with rounds of
heavy lake effect snow through next weekend. The Great Lakes are=20
currently mostly ice free (total ice cover estimated at 14% on Jan=20
17), with surface water temperatures between 2-6C (warmer over=20
southern Lake Michigan and Lake Ontario).

A long wave trough shifts east of the Great Lakes this morning
while the next reinforcing trough swings east across the extent of
the Lakes this afternoon through Monday. NWly flow brings Day 1=20
PWPF for >6" around 50% to the western U.P. (particularly the=20
Porcupine Mtns) and the western shore of the L.P.=20

The flow shifts westerly for Monday shifting the LES focus to the=20
eastern U.P. northern L.P. and for the eastern Great Lakes for=20
Monday with westerly single banding bringing 50-80% probs for >6"=20
to ares south of Buffalo and on the Tug Hill through Watertown.=20

A brief lull in LES sweeps across the Lakes Tuesday, though
single-banding persists on the Eastern Great Lakes. In particular,
the Tug Hill should see notable Day 3 snow with 60% probs for >12".=20


...Southeast, Mid-Atlantic, Northeast...
Day 1...

Positively-tilted full-latitude trough over the Mid-South=20
swing to neutral today as it shifts over the Southeast. Moisture
plume ahead of the trough is mainly rain, but with surface low
pressure developing off the GA coast, the back side of the precip
should turn into moderate bands of snow, particularly from the FL
Panhandle through central GA and the central Carolinas. With these
cases, even with surface temperatures just above freezing, dynamic
cooling could easily bring snow to the surface and accumulate via=20
decent rates of 0.5-0.75"/hr per the 00Z HREF. Day 1 PWPF for >2"
is around 10% in south-central GA and 20% in north-central NC into
southeast VA.

Further up the coast, precipitation will expand northeastward in=20
the right entrance of the >160kt jet atop marginal to cold=20
temperatures (milder along/east of I-95 in the Mid-Atlantic) and
increasing lower to mid-level FGEN. Elongated baroclinic zone and=20
the offshore surface low that rapidly develops as it passes Cape
Hatteras this afternoon and just outside the 40/70 benchmark=20
this evening. The westward extent of the precip shield, where the
snow bands will be is still prominent in 00Z guidance along the
extend of the Mid-Atlantic coast this afternoon and much of New
England late this afternoon through this evening. 00Z HREF mean snow
rates exceed 0.5"/hr over the Delmarva and NJ early this evening
and Long Island/southern New England late this evening through
midnight. Day 1 PWPF for >2" are 40% and up from Philly through
eastern Maine with 50% and up for >4" from NYC through CT/MA/RI and
along the immediate Maine coast. The max for the Day 1 PWPF is from
Providence to Boston where >6" probs are around 60%.=20


...Northern Plains...
Day 1...

**Snow squalls and blizzard conditions likely across parts of the=20
northern Plains today. Key Messages linked below***

The next arctic cold front surges south across the northern Plains
today, with scattered snow squalls mainly this morning from eastern
Montana through the western Dakotas into central Nebraska. The
broad wind field with this front should also trigger blowing snow,
which when combined with additional falling snow could create
blizzard conditions, particularly in the WFO FGF CWA (please see weather.gov/fgf for more info there).=20

Lapse rates reach or exceed 6-7C/km for a brief period along the=20
front and SNSQ parameters rise above 4-5 between eastern MT and=20
central NE. These parameters combined with low-to-mid level FGEN=20 intersecting with a healthy 100mb wide DGZ should allow for=20
efficient snowfall rates within these showers and bands. Wind gusts
up to 60 mph are also possible with this system, adding to the=20
blowing snow potential.

Snow squalls are particularly dangerous for those traveling on
roadways, with extremely low visibilities and slippery conditions
developing rapidly. Be sure to slow down, turn on your lights, and
exit the highway if possible should you get caught in a snow
squall.


...Central High Plains...
Days 1-2...

Cold air surges over the High Plains/against the front ranges of=20
the Rockies today ahead of a reinforcing shortwave trough that
shifts south over the Rockies tonight through Monday. Right=20
entrance jet dynamics over the front will allow banded snow to=20
develop over central MT/WY this evening with stronger banding=20
overnight from northern CO terrain through western KS with snow
bands lingering Monday morning over southwest KS into western OK.=20
The WNWly orientation of these bands is parallel to the flow and=20
should allow for persistence of narrow bands of moderate to=20
locally heavy snow. Day 1 PWPF for >2" remain limited to 30% over=20
the CO Front Range and east of the Palmer Divide in CO/western KS.
CAMs generally struggled with these synoptically driven bands that
have a risk for high performance given the motion along
orientation, so there remains a threat for 4"+ in persistent=20
banding scenarios.

Jackson



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!8mgHyoidHlr2hQD8QC6_PkFw3gcML7nZY0LgmJfp3PNA_= 50yuIFMLCOpfSkQNcKumw5V4v5BVTNpxp0ITTZIl5fYnzo$=20



$$

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FOUS11 KWBC 181903
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
203 PM EST Sun Jan 18 2026

Valid 00Z Mon Jan 19 2026 - 00Z Thu Jan 22 2026


...Great Lakes...
Days 1-3...

Shortwave trough passages around an anchored deep low over Hudson
Bay maintains cyclonic flow through the Great Lakes with rounds of
heavy lake effect snow through at least the first part of the week.
The Great Lakes are currently mostly ice free (total ice cover
estimated at 14%), with surface water temperatures between 2-6C
(warmer over southern Lake Michigan and Lake Ontario). 850mb
temperatures of -20C or so will be quite sufficient for a delta T.

The next reinforcing trough swings east across the extent of the
Lakes tonight/tomorrow along with a surface front. Post-FROPA NW
flow through early Tuesday will promote multi-banded snow into the
U.P. and western Lower Michigan where WPC probabilities for at
least 6 inches of snow through 12Z Tue are >70%. For Lakes
Erie/Ontario, SW flow ahead of the system tonight will keep the
bands mostly in Canada except for around Buffalo/Niagara Falls
before sinking back southward Monday afternoon/evening and
eventually waning on Tuesday (lastly over the Tug Hill). WPC
probabilities for at least 6 inches of snow through 00Z Wed are

90% over the Tug Hill and near/just south of Buffalo. Over the Tug

Hill where the band could persist the longest, WPC probabilities
for at least 18 inches of snow are >50%.

After a brief lull Tuesday evening in the western Lakes, another
system will move through the region overnight and into Wednesday
with the surface low lifting from the Corn Belt across Lake
Michigan through Lower Michigan. Synoptic snow will be followed by
lake effect snow on Wednesday with the highest probabilities for at
least 4 inches of snow over western Lower Michigan near the track
of the area of low pressure (>60% probs).


...Eastern New England...
Day 1...

Deepening area of low pressure just outside the 40/70 benchmark at
00Z tonight will lift quickly northeastward into Atlantic Canada
overnight. Light to modest snow and snow rates (near 1"/hr) atop
cold to marginal surface temperatures over southeastern and eastern
New England will continue snow through the early overnight hours
before winding down by 12Z Monday. WPC probabilities for an
additional 4 inches of snow after 00Z are >50% over eastern MA and
northern RI (except for the Cape and Islands) and along eastern
coastal Maine.


...Central High Plains...
Day 1...

Arctic front diving through the Plains will bring in colder air to
the High Plains tonight. Right entrance jet dynamics over the
front will allow banded snow to develop over central MT/WY this
evening with stronger banding overnight from northern CO terrain
through western KS with snow bands lingering Monday morning over
southwest KS into western OK. The WNWly orientation of these bands
is parallel to the flow and should allow for persistence of narrow
bands of moderate to locally heavy snow. Day 1 PWPF for >2" remain
limited to 30% over the CO Front Range and 10-20% east of the
Palmer Divide in CO/western KS. CAMs generally struggled with these synoptically driven bands that have a risk for high performance
given the motion along orientation, so there remains a threat for
4"+ in persistent banding scenarios (e.g., NAM nest).

Fracasso


$$

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FOUS11 KWBC 190842
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
342 AM EST Mon Jan 19 2026

Valid 12Z Mon Jan 19 2026 - 12Z Thu Jan 22 2026


...Great Lakes/Upper Midwest...
Days 1-3...

Shortwave trough passages around a deep low over anchored over
Hudson Bay maintain cyclonic flow and Lake Effect Snow across the
Great Lakes snow belts at least into this weekend. The Great Lakes
are ice free away from the narrower bays. 850mb temperatures of
-20C to -25C over surface water temperatures between +2 to 6C will
continue to make for a high delta T and convective development.

A reinforcing trough currently over the U.P. swings east across
the rest of the Lakes today with a leading arctic cold front.
Post- FROPA NW flow through early Tuesday will promote multi-
banded snow into the U.P. and northern Lower Michigan where Day 1
WPC probabilities for >6" are 40-70%.

For Lakes Erie/Ontario, SWly flow veers Wly today with ongoing
single-band LES shifting south of Buffalo and onto the Tug Hill
Plateau. Day 1 PWPF for >6" are 60-80% in these zones. LES
continues through Tuesday night, so Day 2 PWPF for >6" are
especially highlighted over the Tug Hill with values over 80%.

A brief lull occurs Tuesday evening in the western Lakes under
brief ridging until the next shortwave/a clipper system shifts east
through the region Tuesday night through Wednesday. A surface low
lifts from Iowa across the L.P. through that time with synoptic
snow bands across northern Iowa and southern Wisconsin where Day
2.5 snow probs for >4" have risen to 20%. Brief LES can be expected
Wednesday into Wednesday night where Day 3 PWPF for >4" are 40-70%
in the western U.P., the length of the western L.P. shore, and east
of Lakes Erie and Ontario.

Yet another clipper is quick on the heels on a similar path to the
previous with snow bands likely over northern Iowa, southern
Wisconsin and souther Michigan again Wednesday night.


...Central High Plains...
Day 1...

Right entrance jet dynamics continue to provide lift over a
baroclinic zone on the central High Plains as high pressure builds
south over the Northern Plains. A decent swath of snow with narrow
embedded bands of moderate to locally heavy snow have developed
from northern CO Front Range to western KS. These will persist into
or through the morning as should slowly sag south to southwestern
KS as the jet also shifts south with the shortwave trough pushing
down the Rockies. An additional few inches can be expected in the
better bands.


The probability of significant icing is less than 10 percent.


Jackson




$$

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FOUS11 KWBC 210923
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
423 AM EST Wed Jan 21 2026

Valid 12Z Wed Jan 21 2026 - 12Z Sat Jan 24 2026


***At Least Major Winter Storm Impacts The South Friday Through=20
This Weekend, Expanding Up The East Coast Saturday Night***

...Southern Rockies, Southern Plains, Through the Mid-South and
Gulf Coast into The Tennessee Valley...=20
Days 2-3...

Precip onset for major winter storm Friday on the Southern Plains=20
and Southern Rockies, quickly intensifying and expanding east over
the Mid-South and Gulf Coast states into the Tennessee Valley=20
Saturday. Expansive cold air mass spills down the Plains Thursday=20
night from 1052mb high pushing into North Dakota. Meanwhile, a=20
cutoff low under a deep ridge off the West Coast approaching=20
southern CA Thursday gets absorbed into the flow of a northern=20
stream trough dropping down the northern Rockies Friday making the=20
united trough full-latitude (through the length of the CONUS) by=20
Saturday. Subtropical East Pacific moisture ahead of the low trough
will spread across northern Mexico with Gulf moisture surging=20
north as early as Thursday night. Persistent Pacific and Gulf=20
moisture overrunning the arctic-sourced airmass will result the=20
full wintry p-type scenario from plain rain near the Gulf Coast to=20
freezing rain not too far inland, to sleet north of that and=20
finally snow where the warm nose remains subzero. The main notes=20
for the 00Z cycle is a northward shift in both QPF and the thermal=20 profiles/warm nose. However, the surface cold air should continue=20
to progress so in a sense the broadness of the winter weather swath
is still expanding (stretching from the Gulf Coast to the central=20
Plains). The precip intensification Friday night through Saturday=20
will be remarkable over the southern Plains and Mid-South with=20
heavy rates and likely catastrophic impacts for at least local=20
scales given the risk for over an inch of ice accretion and deep=20
snow with heavy sleet in between. Residents should prepare for=20
prolonged power outages that occur during the coldest air of the=20
season. Please monitor the forecast for your area via weather.gov.=20
With so much heavy precip occurring just after the WWD time range=20
ending 12Z Saturday, probabilities will be presented through 00Z=20
Sunday (Day 3.5). Day 3.5 PWPF for > 8" is 50-80% across much of=20
the central/southern CO Rockies through the central NM ranges with=20
a wide swath of 20-50% from much of OK, northern AR along the TN/KY
border to the southern Appalachians. Day 3.5 PWPF for >0.5" is=20
20-50% from northeast TX across the LA/AR border and northern MS=20
and northwest AL.=20


...Great Lakes...=20
Days 1-3...

Sprawling Hudson Bay vortex dominates the continental pattern
through this week. Within the broad cyclonic pattern, a pair of=20 shortwaves/clippers cross the Great Lakes through tonight with=20
associated 850-700 mb frontogenesis driving east-west oriented=20
snow bands over WI again and the Great Lakes. Day 1 PWPF for >4"=20
is 50% over southwest MI, northwest PA/western NY and over the Tug
Hill and Mohawk Valley. Northern lake LES continues then through
Friday. Day 2 PWPF for >4" is 50-80% for the Keweenaw and eastern=20
U.P., northern L.P., and the Tug Hill to the western Adirondacks.=20
These values diminish Saturday under surface ridging under the core
of the Arctic cold.


Jackson


...Winter Storm Key Messages remain in effect for extreme cold and
a major winter storm for the south. They are linked below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!6TkyJsUVAAqGEjMXf63mjHBuW427QXBU54gcPNA4JaazV= CZVSrgAWf2a7OjMjHN5lztAe-3wWz8lG44mcV-Fe50kOA0$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!6TkyJsUVAAqGEjMXf63mjHBuW427QXBU54gcPNA4JaazV= CZVSrgAWf2a7OjMjHN5lztAe-3wWz8lG44mcV-F-DbOOYI$=20



$$

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FOUS11 KWBC 212105
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
405 PM EST Wed Jan 21 2026

Valid 00Z Thu Jan 22 2026 - 00Z Sun Jan 25 2026


***Major Winter Storm To Bring Significant Impacts To The South
Friday Through This Weekend, Expanding Up The East Coast Saturday
Night Into Sunday***

...Southern Rockies, Southern Plains, Gulf Coast, Mid-South,
Southern & Central Appalachians, & Mid-Atlantic...
Days 2-3...

The ingredients for the impending major winter storm begin to take
shape Thursday night. A broad upper trough located off Baja
California will work in tandem with a ridge axis near Mexico to
direct a rich plume of tropical East Pacific moisture into the
Southern Rockies and Plains. At the same time, an arctic front
ushers in the coldest temperatures this season across the Great=20
Plains with a highly anomalous dome of arctic high pressure=20
building in over the North Central U.S.. As high pressure rushes=20
south, easterly upslope flow induced between the high pressure to=20
the north and lower pressure near California will cause upslope=20
flow into the higher terrain of the CO and NM Rockies with lighter=20
snowfall in the central High Plains. WPC probabilities show high=20
chances (>70%) for snowfall above 9,000ft in the CO/NM Rockies=20
through Saturday afternoon.

Precipitation will blossom over much of KS, OK, and TX Friday, starting
as rain across much of TX initially, but look for precipitation to
transition to snow over KS, northern OK, and the TX Panhandle by=20
Friday afternoon and evening. Farther south, strengthening low-=20
level WAA will over-run the incoming sub-freezing layer in the=20
lowest 2,000ft of the atmosphere from West Texas to as far east as=20
the Mid-South. Sleet will become more prevalent over the Red River=20
Valley, north-central AR, and into western TN, while freezing rain
is the primary preip type from the TX Hill Country through the=20
ArkLaTex and as far east as the TN Valley. Heavy sleet is possible
in some of these areas with multiple inches of sleet possible
through Saturday. The slow progression of the upper trough over=20
Baja California and the bitterly cold arctic air-mass anchored=20
over the eastern two-thirds of the CONUS is a recipe ripe for=20
prolonged freezing rain from central TX to as far east as the=20
southern Appalachians through 00Z Sunday. WPC probabilities show=20 concerningly high probabilities (50-70%) for ice accumulations=20
through 00Z Sunday over one-quarter inch. The areas of greatest=20
concern are over the ArkLaTx, southern AR, northern LA, northern=20
MS/AL, and southern TN where low-to-moderate chances (30-50%)=20
exist for over one-half inch of ice. While this discussion is=20
geared to the short term (ending 00Z Sunday) the ice in all these=20
areas are forecast to continue through Saturday night and even into
Sunday. There is great concern for extensive tree damage and power
outages from central TX on east through the Mid-South and into the
Southern Appalachians into Sunday.

Farther north, the air-mass through the depth of the atmospheric
column remains cold enough to support all snow from the Central
Plains on east through the Ozarks and across northern TN and much
of KY beginning Friday evening in the Plains, then into the TN/OH
Valleys Saturday morning. By midday and into Saturday afternoon,
periods of snow will reach the southern and central Appalachians
and potentially the VA/NC Piedmont. Snowfall rates topping 1"/hr=20
are likely in areas just north of the strongest 850-700mb FGEN=20
zone and vertical velocities are highest in a highly saturated=20
dendritic growth zone in the Central Plains and OH Valley. The=20
very cold temperatures over KS on east through MS and into the OH=20
Valley will cause SLRs to range anywhere from between 12-18:1 with=20
the higher SLRs over KS. WPC probabilities through 00Z Sunday=20
depict high chances (>70%) for >4" of snow over central and=20
southern KS, much of northern OK, the TX Panhandle, and into the=20
Ozarks of northern AR and southern MO. The best chances for >8" of=20
snowfall reside over the Ozarks where moderate chance probabilities
(40-60%) are present.=20

Similar to the ice, the snow will by no means be over given the=20
extensive plume of anomalous moisture emanating out of the East=20
Pacific. By Saturday night, southerly flow out of the Gulf will=20
continue to direct copious amounts of moisture into the eastern
U.S., resulting in a highly disruptive and dangerous winter storm
from the Mid-South to the Mid-Atlantic. WPC continues to issue Key
Messages for this winter storm and a link to them can be found
below.


...Great Lakes...=20
Days 1-3...

A Hudson Bay vortex pivoting south through Ontario will sustain the
seemingly endless cyclonic flow over the Great Lakes and their
usual snow belts. 500mb heights associated with this powerful upper
low are quite anomalous (below the 1st climatological percentile
in southern Ontario Thursday into Friday night). WPC probabilities
highlight high chances (>70%) for snowfall totals >4" over the
northern tier of the U.P., western MI, along the Chautauqua Ridge
on north into western NY, and down wind of Lake Ontario over the
Tug Hill. The Tug Hill most notably will continue to receive very
heavy snow over the next few days highlighted by WPC 72-hour
probabilities sporting high chances (>70%) in the Tug Hill. A
growing concern is for snow squalls over the Northeast. WPC
initiated Key Messages for what appear to be multiple rounds of
snow squalls from western NY on east through New England, with=20
some squalls possible as far south as northern PA. The final round
of squalls are expected on Friday as an arctic front traverses the
region, causing steep lapse rates and focused vertical ascent. For
more details on the snow squall threat in the Northeast through
Friday, please refer to our Key Messages.


Mullinax



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!4leUoWpjIV7yE2h8DceGN34RPg1d4yvNkmbTFjbw31Qzn= tpehh7jECz3HdwJRagEcw4-6zFuFEKoWCJC7xOHFH7tjJY$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!4leUoWpjIV7yE2h8DceGN34RPg1d4yvNkmbTFjbw31Qzn= tpehh7jECz3HdwJRagEcw4-6zFuFEKoWCJC7xOHAW-kv9A$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!4leUoWpjIV7yE2h8DceGN34RPg1d4yvNkmbTFjbw31Qzn= tpehh7jECz3HdwJRagEcw4-6zFuFEKoWCJC7xOHnzl7X1Y$=20



$$

=3D =3D =3D
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FOUS11 KWBC 220845
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
345 AM EST Thu Jan 22 2026

Valid 12Z Thu Jan 22 2026 - 12Z Sun Jan 25 2026


***Significant Winter Storm To Bring Potentially Crippling Impacts
To Parts Of The South Friday Through This Weekend, Expanding Up=20
The East Coast Saturday Night Into Sunday***

...Southern Rockies and Southern Plains through the Ohio/Tennessee
Valleys into the Mid-Atlantic...
Days 2-3...

Estimated over 130 million residents under winter weather headlines
this morning as confidence continues to increase on a highly=20
impactful and extremely wide- reaching winter storm to begin on=20
Friday across the south-central U.S., eventually pushing towards=20
the East Coast by Saturday night into Sunday. Guidance has nearly=20 unanimously converged on the upper low churning just west of=20
southern CA (sampled by recon aircraft for the recent 00z model=20
suite) to eject eastward ahead of a diving northern stream=20
shortwave and fully phase by the day 4 timeframe. Uncertainty=20
remains associated with the speed of the approaching northern=20
stream trough, which eventually leads to the amplified pattern in=20
the central/eastern U.S.. However, this uncertainty has decreased=20
tonight as guidance converges on cluster 1 from WPC's 12z 1/21=20
clusters. Some guidance remains more amped (CMC/ECMWF) than others=20
(GFS) and leads to some lingering uncertainty regarding the=20
northern extent of heavy QPF and the mid- level warm nose. However,
all scenarios now point to a large QPF footprint falling in the=20
form of frozen precipitation and resulting in a significant winter
storm.

The aforementioned southern CA upper low will help surge ample=20
Pacific moisture (above the 90th climatological percentile per the=20
12z NAEFS) into the southern U.S. by Friday night, where a deep=20
arctic airmass is placed in ideal position for overrunning and=20
wintry precipitation. This arctic airmass in place is brought to=20
the region by a near record 1050mb surface high pressure over the=20
Northern Plains on Friday. As time progresses this high pressure is
expected to moderate and evolve into more of a "banana" look,=20
which is classic for heavy winter precipitation in the East as
low-levl cold air continues to sink southward towards a stationary
front forecast to stretch along the Gulf Coast. A few weak areas of
low pressure are forecast to form along this front before gradually
lifting northward into the TN Valley and along the Carolina=20
coastline by the end of D3. Decided to split up the remainder of=20
the discussion into hazard- type categories given this event covers
such a massive amount of real- estate. For local forecasts and=20
more details, read your local WFOs AFD.

Heavy Freezing Rain/Sleet...
Arguably the most lasting impact associated with this winter storm
could be from heavy accumulating freezing rain and sleet=20
stretching from the southern Plains, Mid-South, Tennessee Valley,=20
and southern Mid- Atlantic. This is due to very cold low-level=20
arctic air being reinforced by the strong high over the north-=20
central U.S. and a warm nose aloft (at around 750mb per cross=20
section model soundings) melting snow as it falls through the=20
column before refreezing just before or at the surface. The=20
greatest freezing rain amounts and impacts are currently forecast=20
across northeast TX through northern MS as favorable thermal=20
profiles linger for over 24 hours beginning Friday night. WPC=20
72-hour probabilities for >0.5" of freezing rain are high >70%=20
across southern AR into parts of northwest MS. Here, ice accretion=20
could be crippling and exceed 0.75-1.00", which would very likely=20
lead to widespread long- lasting damage to infrastructure,=20
including power outages and tree damage. Major sleet accumulations
are also likely just north of the freezing rain area stretching=20
from southern OK/north TX through central AR and into the Mid-
South, with more than a few inches of sleet possible. This could=20
make for treacherous driving conditions and lasting travel impacts=20
due to the bitterly cold airmass expected to linger into next week=20
over the region.

Heavy icing is also likely into the TN Valley and nearby southern=20 Appalachians and Mid- Atlantic, where freezing rain continues=20
beyond the D3 timeframe. The setup across the southern Mid-Atlantic
down as far south as northern GA and areas just inland from the=20
coasts of the Carolinas is an extreme case of CAD with a 1040mb=20
high situated over the Interior Northeast on Saturday night. This=20
high pressure filters very low/dry dew points with values below
zero prior to precip onset late Saturday. This cold air wedge
remains sharply locked in place at the surface for the remainder=20
of the event as 700-850mb temperatures begin to increase well above
freezing by the end of D3 throughout the Carolinas and northern=20
GA. WPC probabilities for >0.25" of freezing rain accretion through
12z Sun. are currently 40-70% from northern AL/TN through northern
GA and into the Midlands of SC and areas just inland of the NC=20
Tidewater region. Heavy sleet accumulations are also possible where
the low-level column remains colder into VA Piedmont.

Heavy Snow...
North of the mixed precipitation area and closely tide to both a=20
favorable LFQ of a zonally oriented 180kt upper jet and strong=20
700mb fgen, snow is the primary precipitation type stretching from=20
the southern High Plains of east-central NM and the southern=20
Rockies through the Plains, Mid-Mississippi Valley, Ohio Valley,=20
and Mid-Atlantic by Sunday morning. Favorable upslope flow as the=20
strong arctic high pressure noses southward along the High Plains=20
starts on Friday across the southern Rockies, with light snow and=20
even a chance for freezing drizzle at onset across the central=20
Plains until the column fully saturates. Heavy snow is then=20
forecast to begin breaking out Friday night from the=20
central/southern Plains through the mid-Mississippi Valley and=20
spanning much of the Ohio Valley and parts of the Midwest on=20
Saturday. Snowfall rates could near 1"/hr as strong lift intersects
with a region about 150 miles north of the mixed precip zone where=20
the DGZ is forecast to be extremely deep (about 500 mb per areal=20
average soundings). This would allow for efficient formation of=20
dendrites where ample lift can fully moisture the column. Should a=20
region remain in this zone for a longer enough period it's not out=20
of the realm of possibility 30:1 snow ratios are observed.=20
However, most locations appears to progressively see this favorable
DGZ move east-northeast with time and shrink as mid-level=20
temperatures increase above -8C and allows for more needles than=20
dendrites. WPC probabilities for >6" of snow through 12z Sun. are=20
medium to high (30-70%) stretching from east-central NM and the TX=20
Panhandle across northern OK, into the Mid-Mississippi Valley.=20
These probabilities increase to above 70% in the Ohio Valley,=20
where 8-10" of snow is possible. The widespread nature of this
heavy snow is likely to significantly impact both ground and air
travel in the region.

One area that is slowly becoming the most favorable location for=20
heavy snowfall rates and potentially the most impressive snowfall=20
amounts is the central Appalachians, northern VA, MD, and southern=20
PA through early Sunday. As the upper level trough deepens over the
central U.S. Saturday night, mid- level flow begins to increase=20
out ahead of it and meets the mid-level warm front stretching from
the eastern Ohio Valley into the Mid- Atlantic. Several 00z models
highlight increasing 700mb fgen over the eastern Ohio Valley and=20
into central VA by late D3, which supports the potential for an=20
extended period of 1"/hr rates across much of eastern WV,=20
central/northern VA, MD, and southern PA. The 0C warm nose may=20
begin to approach northern VA by the end of D3, but areas just to=20
the north could see 6-12" by sunrise on Sunday as precipitation=20
lingering further into the day on Sunday. Snow ratios will also be
favorable at onset and could potentially exceed 20:1 within
enhanced banding, which is well above the 11:1 climatology in the
region. Current WPC probabilities through D3 are medium to high=20
(40-70%) for at least 8" of snow, this includes areas just west of=20
I-95 from D.C. to Baltimore. Heavy snow is expected to continue=20
stretching into the Northeast and New England on Sunday, see WPC's=20
Extended Forecast Discussion for more. Also, see the Key Messages=20
linked at the bottom of this discussion.


...Great Lakes...=20
Days 1-2...

A Hudson Bay vortex pivoting south through Ontario will sustain the
seemingly endless cyclonic flow over the Great Lakes and their
usual snow belts before strong high pressure builds overhead on D3
and ends this lake effect pattern for the time being. 500mb=20
heights associated with this powerful upper low are quite anomalous
(below the 1st climatological percentile per 12z NAEFS in southern
Ontario Thursday into Friday night). WPC probabilities highlight=20
medium-high chances (>60%) for snowfall totals >6" over the=20
northern tier of the U.P., along the Chautauqua Ridge on north=20
into western NY, and down wind of Lake Ontario over the Tug Hill.=20
The Tug Hill most notably will continue to receive very heavy snow=20
over the next few days highlighted by WPC 48-hour probabilities=20
sporting high chances (>70%) for >8" in the Tug Hill.=20

A growing concern is for snow squalls over the Northeast. WPC=20
initiated Key Messages for what appear to be multiple rounds of=20
snow squalls from western NY on east through New England, with some
squalls possible as far south as northern PA early today. This is
highlighted well in CAMs snow squall parameter, with highest
potential on Thursday from western PA through central NY. The=20
final round of squalls are expected on Friday as an arctic front=20
traverses the region, causing steep lapse rates and focused=20
vertical ascent. This front will also usher dangerously cold
temperatures and wind chills. For more details on the snow squall=20
threat in the Northeast through Friday, please refer to our Key=20
Messages.


Snell




...Winter Storm/Snow Squall/Extreme Cold Key Messages are in=20
effect. Please see current Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!4SOx9iXiM3PgwTKiPMC2-PfsGt8BJz0BBMMz9h4kUUIjD= IQTQvpLmpBzti1jhxxLn8WLhLWkb5WyZSxjoet_GDZdtno$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!4SOx9iXiM3PgwTKiPMC2-PfsGt8BJz0BBMMz9h4kUUIjD= IQTQvpLmpBzti1jhxxLn8WLhLWkb5WyZSxjoet_AHZ3rCs$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!4SOx9iXiM3PgwTKiPMC2-PfsGt8BJz0BBMMz9h4kUUIjD= IQTQvpLmpBzti1jhxxLn8WLhLWkb5WyZSxjoet_3CqF82U$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
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FOUS11 KWBC 221959
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
259 PM EST Thu Jan 22 2026

Valid 00Z Fri Jan 23 2026 - 00Z Mon Jan 26 2026


...Major winter storm to bring the potential for crippling icing,=20 significant sleet, and heavy snow from the Southern Plains through=20
the Southeast and up the Atlantic Coast into New England...

The event will begin Friday morning across the Southern Plains. The
driver of this event is an impressive overlap of intensifying
synoptic ascent with increasing subtropical moisture.=20

The synoptic pattern becomes favorable Friday in response to the
evolution of multiple shortwaves rotating through an amplifying
trough across the eastern CONUS. A closed 500mb low off the Baja
Peninsula will begin to open and shear to the east, at the same
time dual shortwaves dig out of Saskatchewan/Alberta and into the
Northern Plains. As the northern shortwaves dive south and the Baja
low ejects east, the interaction of these features will lead to
increasing mid-level divergence overlapping pronounced height falls
to produce rich deep layer lift. This will be on top of an arctic
cold front that will be sagging southward into the Southern Plains
and eventually work its way southeast to the Gulf and Atlantic
coasts by Saturday. This overlapping ascent will materialize atop a
moistening column as subtropical moisture downstream of the Baja
low streams northeast reflected by IVT that reaches above the 97th
percentile according to NAEFS, in a broad swath from Texas to the
Carolinas, with above the record (CFSR at 00Z) climatology by
Sunday evening in the east.=20

This increasing moisture will result in a large swath of
precipitation expanding from the Southern Plains Friday, to the
Mississippi Valley and Tennessee Valley Saturday, into the
Carolinas and Mid-Atlantic by Sunday, and finally reaching the
Northeast Sunday night. This is a very large and impactful system
across a huge portion of this country. While impacts will be
considerable in many areas (aided by extreme cold), the icing (and
sleet) and snow will be most impressive across two distinct areas.

Freezing Rain and Sleet:
Arguably the most lasting impact associated with this winter storm
could be from heavy accumulating freezing rain and sleet stretching
from the southern Plains, Mid- South, Tennessee Valley, and
southern Mid-Atlantic. This is due to very cold low-level arctic
air being reinforced by the strong high over the north-central U.S.
(and enhanced by pronounced mid-level confluence over the Great
Lakes and New England) and a warm nose aloft (at around 750mb per
cross section model soundings) melting snow as it falls through the
column before refreezing just before or at the surface,and in some
places this re-freezing layer is above the 90th percentile in terms
of depth, suggesting some locations will experience exceptional
sleet accumulations.=20

The greatest freezing rain amounts and impacts are currently=20
forecast across northeast TX through northern MS as favorable=20
thermal profiles linger for over 24 hours beginning Friday night.=20
WPC 72-hour probabilities for >0.5" of freezing rain are high >70%=20
across southern AR into parts of northwest MS. Here, ice accretion=20
could be crippling and exceed 0.75-1.00", (WPC probabilities above
50% for 1" if ice) which would almost certainly lead to widespread
long-lasting damage to infrastructure, including power outages and
tree damage. Major sleet accumulations are also likely just north=20
of the freezing rain area stretching from southern OK/north TX=20
through central AR and into the Mid- South, with more than a few=20
inches of sleet possible. The consistency of the guidance in both=20
placement and amounts for this area are resulting in high=20
confidence in an extreme event, leading to long-lasting impacts=20
both to travel and infrastructure due to the bitterly cold airmass=20
expected to linger into next week over the region.

Heavy icing is also expected farther east into the southern=20
Appalachians and southern Mid-Atlantic. The setup across the=20
southern Mid- Atlantic down as far south as northern GA and areas=20
just inland from the coasts of the Carolinas is an extreme case of=20
CAD with a 1040mb high situated over the Interior Northeast on=20
Saturday night. While regional soundings indicate there may be
considerable sleet in this area as well, especially across southern
VA into northern NC, these CADs are notorious for their effective dry/isallobaric flow, enhanced by precipitation, leading to dry
wet-bulb advection offsetting the latent heat of freezing during
freezing rain. With such an impressive high in place at
precipitation onset, this will likely result in considerable
accumulations of sleet and freezing rain here, too, with WPC
probabilities indicating a moderate risk (50-70%) of at least 0.5",
highest across the Piedmont. The guidance has trended just a bit
colder this afternoon, but significant icing is also possible as
far north as Richmond, VA and towards the Chesapeake Bay.


Heavy Snow:
North of the mixed precipitation area and closely tied to both a
favorable LFQ of a zonally oriented 180kt upper jet and strong
700mb fgen, snow is the primary precipitation type stretching from
the southern High Plains of east-central NM and the southern
Rockies through the Plains, Mid-Mississippi Valley, Ohio Valley,
Mid-Atlantic, and reaching the Northeast by Sunday evening (with
additional expansion beyond this forecast period).=20

Favorable upslope flow as the strong arctic high pressure noses=20
southward along the High Plains behind a strong cold front starts=20
on Friday across the southern Rockies, with light snow and even a=20
chance for freezing drizzle at onset across the central Plains=20
until the column fully saturates. Heavy snow is then forecast to=20
begin breaking out Friday night from the central/southern Plains=20
through the mid-Mississippi Valley and spanning much of the Ohio=20
Valley and parts of the Midwest on Saturday. Snowfall rates could=20
near 1"/hr as strong lift through WAA/fgen intersects with a=20
region where the DGZ is forecast to be extremely deep (SREF
probabilities above 70% for >100mb of depth). This would allow for
efficient formation of dendrites where ample lift can fully=20
moisture the column. While this depth is impressive, regional
forecast soundings indicate that the best ascent may lie below this
DGZ in many areas, and there is only modest indication of any
isothermal layer beneath the DGZ to maintain aggregates. Despite
this, efficient and fluffy SLRs are likely in this area, and with a
long duration event expected, WPC probabilities are moderate
(30-50% )for at least 12 inches from eastern KS and OK into=20
southern MO, with widespread 4+ inches extending all the way back
into the TX Panhandle and lower MS VLY.

Farther east, some heavier snowfall is becoming more likely for
parts of the Ohio Valley, and into the Mid-Atlantic, and especially
Northeast. Here, pronounced WAA and accompanying 850-700mb fgen
will drive pronounced ascent into a rapidly moistening column
thanks to IVT above the 90th climatological percentile. As the
upper trough (interaction of the southern and northern streams)
deepens over the Plains, downstream ascent will maximize and a
period of impressive WAA snow with snowfall rates >1"/hr are
likely. As secondary low pressure develops offshore (in a Miller B
type evolution), banded structures within the WAA are likely to
translate northward from the Mid-Atlantic into New England, and
then may pivot and drift eastward Sunday night into Monday. Where
this occurs, the heaviest total snowfall accumulations are
probable, reflected by WPC probabilities that are already above 50%
for 12+ inches, and this is even with more of the event beyond this
forecast period (into New England). While there is some uncertainty
into how much mixing will pivot northward, especially closer to the
coast from Richmond, VA through Long Island, the interior portions
(NW of I-95 and into southern New England which will remain cold as
the secondary low develops and tracks near the 40/70 Benchmark)
will remain all snow with above-climo SLRs leading to significant
snowfall accumulations. Many areas are expected to receive more
than 12 inches from the Ohio Valley through the Mid-Atlantic and
into the Northeast before this system winds down on Monday /D4/.

Key Messages for this system are linked below (Key Message 2)


...Great Lakes...=20
Days 1-2...

Expansive mid-level low centered over the Hudson Bay will track
slowly southward this evening and then begin to shear open and
translate to the east as a secondary shortwave rotates through its
base and atop the Great Lakes Friday evening. Behind this impulse,
shortwave ridging will amplify across the area, bringing an end to
the persistent CAA and associated lake-induced ascent.

The subsequent W/NW flow and accompanying CAA will lead to
impressive lake effect snow (LES) in the favored W/NW snow belts
D1, with some pivoting to more N/NW D2 before waning. The heaviest
snowfall is likely east of Lake Ontario D1 where WPC
probabilities indicate a high risk (>70%) for at least 12 inches,=20
and 1-2 feet is possible across the Tug Hill Plateau. Elsewhere,=20
WPC probabilities suggest a moderate risk (50-70%) for at least 4=20
inches along the Chautauqua Ridge, western MI (east shore of Lake=20
Michigan) and across the northern U.P. During D2 the precipitation=20
intensity will weaken, but WPC probabilities suggest a moderate=20
risk (30-70%) for at least 2 inches in far NW IN and southeast of=20
Lake Ontario, before the shortwave ridging brings an end to this=20
round of LES.

Additionally, and this pivots into the Northeast as well, a second
round of snow squalls is possible on Friday along and behind an
arctic cold front traversing the region. For more details on the=20
snow squall threat in the Northeast through Friday, please refer to
our Key Messages (Key Messages 3) below.


Snell/Weiss





...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!-ZbcCxUHFaZzUCjVjcXjC8-1-t_ZYP0Ds_0gTb0a3UKg7= LWejAi__n66qDCj_90esw97-mNA9zZNPcoKLnZx6xUubt8$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!-ZbcCxUHFaZzUCjVjcXjC8-1-t_ZYP0Ds_0gTb0a3UKg7= LWejAi__n66qDCj_90esw97-mNA9zZNPcoKLnZx7Mmwhog$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!-ZbcCxUHFaZzUCjVjcXjC8-1-t_ZYP0Ds_0gTb0a3UKg7= LWejAi__n66qDCj_90esw97-mNA9zZNPcoKLnZx13dN6Ms$=20



$$

=3D =3D =3D
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FOUS11 KWBC 232057
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
357 PM EST Fri Jan 23 2026

Valid 00Z Sat Jan 24 2026 - 00Z Tue Jan 27 2026


...Major winter storm to bring the potential for crippling icing,=20 significant sleet, and heavy snow from the Southern Plains through=20
the Southeast and up the Atlantic Coast into New England...

Meteorological Overview...

A massive winter storm, set to produce a swath of heavy snow and=20
dangerous ice accumulations, has begun today as tropical East=20
Pacific moisture streams out ahead of the 500mb closed low near the
Baja Peninsula. This moisture plume is clashing with the coldest=20
air-mass of the season, entrenching itself over the Nation's=20
Heartland. The moisture transport is exceptional with an
integrated vapor transport (IVT) above the 97.5 climatological=20
percentile per ECMWF SATs. The rich moisture from the south will=20
accompany strong 850-700mb WAA that results in classic over-runing=20
along a developing area of 850-700mb FGEN atop the Southern Plains.
Meanwhile, the upper trough in the Southwest and an emerging=20
upper- level shortwave trough over the Dakotas will strengthen a=20
250mb jet streak over the east-central U.S., placing its thermally-
direct right-entrance region over the Southern Plains. This=20
synoptic- scale setup helps to enhance the mesoscale below,=20
fostering heavy bands of snow and even elevated instability above=20
the low-level sub-freezing layer over north TX on east into the=20
Mid-South tonight and into Saturday.

By Saturday, as the upper low near Baja approaches Texas, its=20
associated jet streak over Mexico will co-locate its divergent=20
left-exit region over the Mid-South and maximize upper-level ascent
over the region. The IVT in advance of the upper trough over=20
Mexico is both expansive and strong with >90th climatological=20
percentile IVT values originating south of Mexico and extending all
the way to the Southern Appalachians by Saturday afternoon. The=20
remarkable extent of the IVT and the slow progression of the Mexico
trough is why parts of the South and Mid-Atlantic are likely to=20
see snow, sleet, and freezing rain for over 24 hours and in some=20
cases approaching 48 hours. As arctic high pressure slides east, a=20
cold-air damming (CAD) signature will become well pronounced along=20
and east of the Appalachians as anomalous Pacific and Gulf moisture
arrives, leading to precipitation falling into the frigid air-mass
and supporting heavy snow, sleet, and freezing rain totals from=20
the southern Appalachians to the Mid-Atlantic.=20

Saturday night and into Sunday is where most changes in the
forecast have unfolded of late. It remains unclear just how strong
the emerging area of low pressure near the Gulf Coast will be and=20
how far north it gets. It is noteworthy that guidance is in good=20
agreement on 700mb Q-vector convergence over northern AL and the=20
southern Appalachians, but the GFS is a little farther south in=20
positioning while the ECMWF is a littler farther north and=20
stronger, resulting in the northern shifts over the last couple=20
days. What they do both agree on is by Sunday, a very pronounced=20
area of strong 700mb Q-vector convergence will unfold along the=20
Mid-Atlantic coast, prompting the development of a coastal low=20
along a strengthening coastal front. With the benefit of the 250mb
jet streak's divergent right-entrance region aloft and the=20
strengthening IVT (ECMWF SATs show >99.5 climatological percentile=20
values over the Southeast Sunday morning), an expansive=20
precipitation shield will span across the OH Valley, Mid-Atlantic,=20
and Northeast with excessive amounts of wintry precipitation=20
falling. While there remains some question on precipitation type,=20
the ECMWF EFI shows the QPF is >0.8 from the Southern Plains and=20
Mid-South to the Northeast, implying an unusually high amount of=20
QPF for this time of year will be at this winter storm's disposal=20
as it falls into a bitterly cold Arctic air-mass.=20

Heavy Snow/Sleet...

The latest forecast calls an astonishingly long swath (over 2,000=20
mile long in length) of >6" of snowfall that starts in the Sangre=20
De Cristo and Sacramento mountains of New Mexico all the way to=20
Downeast Maine. It is worth noting that the snowfall probabilities=20
being referenced will have snow and sleet. Focusing on the Plains=20
first, WPC probabilities sport high chances (>70%) for snowfall >8"
over central OK, southeast KS, southwest MO, and northwest AR.=20
There is another impressive swath of high chance probabilities=20

70%) for >8" of snow from southern IN and north-central KY to=20

eastern Maine. The Central Appalachians, interior Northeast, and=20
southern New England are likely to see the most snowfall with high=20
chances (>70%) for over a foot of snow in these areas. In fact, WPC probabilities show low-to-moderate chances (30-50%) for totals=20
over 18" in the Catskills, Berkshires, and eastern MA. Farther=20
south, the inclusion of sleet from NY and Long Island southward=20
along the I-95 corridor will likely cut into snowfall totals.=20 Climatologically speaking, areas west of I-95 where topography=20
increases are most likely to see more snow than sleet. This is=20
evident in the >8" for snow and sleet probabilities where they are=20
high (>70% chances) from northwest VA and north-central MD along=20
Parrs Ridge to the Lower Susquehanna Valley, but below 50% over=20
southern NJ, the MD eastern shore, and south of Fredericksburg, VA.
Still, the WSO shows >50% chances for a warning-level snowfall as=20
far south as central VA on east through the northern DelMarVa and=20
into southern NJ due to the strong 850-700mb FGEN Saturday night=20
and Sunday morning that fosters snowfall rates that could ranges
between 1-2"/hr. So while snowfall/sleet totals are not quite as=20
high as their neighbors to the north, the combination of snow,=20
sleet, and inclusion of some freezing rain still support=20
significant travel disruptions in these southern areas as well.=20

The WSSI shows widespread Major Impacts (considerable disruptions
to daily life: dangerous to impossible driving conditions,=20
widespread closures, and disruptions to infrastructure) from the TX
Panhandle on east to the Ozarks, through the OH Valley, and all the
way to New England. Every major market along the I-95 metropolitan
corridor (Washington D.C. to Boston and even as far north as
Portland, ME) are expecting major impacts due to snow. The=20
D.C/Baltimore area on north to Philly and NYC are likely to see=20
some inclusion of sleet, but it will still result in significant=20
impacts when accounting for heavy snowfall that is expected to
exceed warning criteria (5-6"). A reminder that bitterly cold=20
temperatures will follow in wake of this storm Monday and into the=20
middle of the week throughout the eastern U.S.. The snow/sleet=20
impacts will linger well into next week with rounds of re-freezing=20
that keeps surfaces icy and dangerous to both drive and walk on for
the foreseeable future. Those in the path of this storm should=20
make final preparations and put plans in place for significant=20
travel disruptions this weekend and into at least early next week.


Freezing Rain:

The most lasting and dangerous impact will come as a result of=20
significant to locally catastrophic ice accumulations due to=20
prolonged periods of freezing rain. Just like the swath of >6" of=20
snowfall, the areal coverage of high chances (>50%) in WPC's ice=20 probabilities exceeding one-quarter inch of ice accumulation is=20
both impressive and alarming. From east-central TX to southern AR,=20
northern LA, northern MS, the TN Valley, northern GA, the southern=20 Appalachians, and southern Mid-Atlantic, these regions are all=20
likely to experience anywhere from one-quarter to one-half inch of=20
ice. Widespread power outages and tree damage is likely in these=20
areas, especially from the Lower MS Valley, southern Appalachians,=20
and central NC where there are also high chances (>70%) for ice=20 accumulations over one-half inch. It is parts of northern AL,=20
northern MS, south-central TN, far northern GA, the southern=20
Appalachians, and the NC Piedmont that are of greatest concern.=20
WPC probabilities show low-to-moderate chances (20-40%) for ice=20 accumulations over 1 inch. These areas are likely to endure a=20
crippling ice storm that will take days, if not weeks, of clean up=20
in addition to extended power outages. Residents in these areas=20
should take final preparations now. Once the freezing rain starts,=20
dangerous travel will be common not only during the event, but in=20
the days in wake of the storm due to prolonged sub-freezing=20
temperatures that cause persistent re-freezing on all untreated=20
surfaces. The Key Messages for the Extreme Cold are linked below
(Key Message 1).

Farther east, freezing rain will reach southern VA, the DelMarVa
Peninsula, and as far north as southern NJ. The southern VA
Piedmont, including the Richmond metro area, have moderate chances
(40-60%) for over one-half inch of ice. The WSSI depicts Major=20
Impacts from Richmond on south along I-95 into NC, while Moderate=20
Impacts (hazardous travel conditions) are anticipated as far north=20
as the northern DelMarVa Peninsula and into the Lower Delaware=20
Valley. While most areas farther north towards the Lower Delaware=20
Valley and southern NJ should largely remain sleet, it may=20
transition to freezing rain for a brief time by Sunday evening. WPC probabilities show low-to-moderate chances (30-50%) for over one-=20
tench of an inch of ice accumulations Sunday evening.


Key Messages for this system are linked below (Key Message 2)


Mullinax



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!8GUWGIKvjpbH7j06LCzf76dgj7wKmpMcynczXffJXXaY-= mNp6L2dr8o-PiAMPcRJ2YyFHPbCmPdKNKW5sTA1hXXuSxM$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!8GUWGIKvjpbH7j06LCzf76dgj7wKmpMcynczXffJXXaY-= mNp6L2dr8o-PiAMPcRJ2YyFHPbCmPdKNKW5sTA1nTFVkNQ$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!8GUWGIKvjpbH7j06LCzf76dgj7wKmpMcynczXffJXXaY-= mNp6L2dr8o-PiAMPcRJ2YyFHPbCmPdKNKW5sTA1sbzsBKw$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/105)

FOUS11 KWBC 232103
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
403 PM EST Fri Jan 23 2026

Valid 00Z Sat Jan 24 2026 - 00Z Tue Jan 27 2026


...Major winter storm to bring the potential for crippling icing,=20 significant sleet, and heavy snow from the Southern Plains through=20
the Southeast and up the Atlantic Coast into New England...

Meteorological Overview...

A massive winter storm, set to produce a swath of heavy snow and=20
dangerous ice accumulations, has begun today as tropical East=20
Pacific moisture streams out ahead of the 500mb closed low near the
Baja Peninsula. This moisture plume is clashing with the coldest=20
air-mass of the season, entrenching itself over the Nation's=20
Heartland. The moisture transport is exceptional with an
integrated vapor transport (IVT) above the 97.5 climatological=20
percentile per ECMWF SATs. The rich moisture from the south will=20
accompany strong 850-700mb WAA that results in classic over-runing=20
along a developing area of 850-700mb FGEN atop the Southern Plains.
Meanwhile, the upper trough in the Southwest and an emerging=20
upper- level shortwave trough over the Dakotas will strengthen a=20
250mb jet streak over the east-central U.S., placing its thermally-
direct right-entrance region over the Southern Plains. This=20
synoptic- scale setup helps to enhance the mesoscale below,=20
fostering heavy bands of snow and even elevated instability above=20
the low-level sub-freezing layer over north TX on east into the=20
Mid-South tonight and into Saturday.

By Saturday, as the upper low near Baja approaches Texas, its=20
associated jet streak over Mexico will co-locate its divergent=20
left-exit region over the Mid-South and maximize upper-level ascent
over the region. The IVT in advance of the upper trough over=20
Mexico is both expansive and strong with >90th climatological=20
percentile IVT values originating south of Mexico and extending all
the way to the Southern Appalachians by Saturday afternoon. The=20
remarkable extent of the IVT and the slow progression of the Mexico
trough is why parts of the South and Mid-Atlantic are likely to=20
see snow, sleet, and freezing rain for over 24 hours and in some=20
cases approaching 48 hours. As arctic high pressure slides east, a=20
cold-air damming (CAD) signature will become well pronounced along=20
and east of the Appalachians as anomalous Pacific and Gulf moisture
arrives, leading to precipitation falling into the frigid air-mass
and supporting heavy snow, sleet, and freezing rain totals from=20
the southern Appalachians to the Mid-Atlantic.=20

Saturday night and into Sunday is where most changes in the
forecast have unfolded of late. It remains unclear just how strong
the emerging area of low pressure near the Gulf Coast will be and=20
how far north it gets. It is noteworthy that guidance is in good=20
agreement on 700mb Q-vector convergence over northern AL and the=20
southern Appalachians, but the GFS is a little farther south in=20
positioning while the ECMWF is a littler farther north and=20
stronger, resulting in the northern shifts over the last couple=20
days. What they do both agree on is by Sunday, a very pronounced=20
area of strong 700mb Q-vector convergence will unfold along the=20
Mid-Atlantic coast, prompting the development of a coastal low=20
along a strengthening coastal front. With the benefit of the 250mb
jet streak's divergent right-entrance region aloft and the=20
strengthening IVT (ECMWF SATs show >99.5 climatological percentile=20
values over the Southeast Sunday morning), an expansive=20
precipitation shield will span across the OH Valley, Mid-Atlantic,=20
and Northeast with excessive amounts of wintry precipitation=20
falling. While there remains some question on precipitation type,=20
the ECMWF EFI shows the QPF is >0.8 from the Southern Plains and=20
Mid-South to the Northeast, implying an unusually high amount of=20
QPF for this time of year will be at this winter storm's disposal=20
as it falls into a bitterly cold Arctic air-mass.=20

Heavy Snow/Sleet...

The latest forecast calls an astonishingly long swath (over 2,000=20
mile long in length) of >6" of snowfall that starts in the Sangre=20
De Cristo and Sacramento mountains of New Mexico all the way to=20
Downeast Maine. It is worth noting that the snowfall probabilities=20
being referenced will have snow and sleet. Focusing on the Plains=20
first, WPC probabilities sport high chances (>70%) for snowfall >8"
over central OK, southeast KS, southwest MO, and northwest AR.=20
There is another impressive swath of high chance probabilities=20

70%) for >8" of snow from southern IN and north-central KY to=20

eastern Maine. The Central Appalachians, interior Northeast, and=20
southern New England are likely to see the most snowfall with high=20
chances (>70%) for over a foot of snow in these areas. In fact, WPC probabilities show low-to-moderate chances (30-50%) for totals=20
over 18" in the Catskills, Berkshires, and eastern MA. Farther=20
south, the inclusion of sleet from NY and Long Island southward=20
along the I-95 corridor will likely cut into snowfall totals.=20 Climatologically speaking, areas west of I-95 where topography=20
increases are most likely to see more snow than sleet. This is=20
evident in the >8" for snow and sleet probabilities where they are=20
high (>70% chances) from northwest VA and north-central MD along=20
Parrs Ridge to the Lower Susquehanna Valley, but below 50% over=20
southern NJ, the MD eastern shore, and south of Fredericksburg, VA.
Still, the WSO shows >50% chances for a warning-level snowfall as=20
far south as central VA on east through the northern DelMarVa and=20
into southern NJ due to the strong 850-700mb FGEN Saturday night=20
and Sunday morning that fosters snowfall rates that could ranges
between 1-2"/hr. So while snowfall/sleet totals are not quite as=20
high as their neighbors to the north, the combination of snow,=20
sleet, and inclusion of some freezing rain still support=20
significant travel disruptions in these southern areas as well.=20

The WSSI shows widespread Major Impacts (considerable disruptions
to daily life: dangerous to impossible driving conditions,=20
widespread closures, and disruptions to infrastructure) from the TX
Panhandle on east to the Ozarks, through the OH Valley, and all the
way to New England. Every major market along the I-95 metropolitan
corridor (Washington D.C. to Boston and even as far north as
Portland, ME) are expecting major impacts due to snow. The=20
D.C/Baltimore area on north to Philly and NYC are likely to see=20
some inclusion of sleet, but it will still result in significant=20
impacts when accounting for heavy snowfall that is expected to
exceed warning criteria (5-6"). A reminder that bitterly cold=20
temperatures will follow in wake of this storm Monday and into the=20
middle of the week throughout the eastern U.S.. The snow/sleet=20
impacts will linger well into next week with rounds of re-freezing=20
that keeps surfaces icy and dangerous to both drive and walk on for
the foreseeable future. Those in the path of this storm should=20
make final preparations and put plans in place for significant=20
travel disruptions this weekend and into at least early next week.


Freezing Rain...

The most lasting and dangerous impact will come as a result of=20
significant to locally catastrophic ice accumulations due to=20
prolonged periods of freezing rain. Just like the swath of >6" of=20
snowfall, the areal coverage of high chances (>50%) in WPC's ice=20 probabilities exceeding one-quarter inch of ice accumulation is=20
both impressive and alarming. From east-central TX to southern AR,=20
northern LA, northern MS, the TN Valley, northern GA, the southern=20 Appalachians, and southern Mid-Atlantic, these regions are all=20
likely to experience anywhere from one-quarter to one-half inch of=20
ice. Widespread power outages and tree damage is likely in these=20
areas, especially from the Lower MS Valley, southern Appalachians,=20
and central NC where there are also high chances (>70%) for ice=20 accumulations over one-half inch.=20

It is parts of northern AL, northern MS, south-central TN, far=20
northern GA, the southern Appalachians, and the NC Piedmont that=20
are of greatest concern. WPC probabilities show low-to-moderate=20
chances (20-40%) for ice accumulations over 1 inch. These areas are
likely to endure a crippling ice storm that will take days, if not
weeks, of clean up in addition to extended power outages. This is=20 demonstrated in a rare Extreme Impact on the WSSI in parts of
northern MS, far southern TN, and the Southern Appalachians. The
WSSI Extreme criteria references the potential for "extensive and=20
widespread closures, extremely dangerous travel, and life-saving=20
actions may be needed." Residents in these all referenced regions=20
above should take final preparations now. Once the freezing rain=20
starts, dangerous travel will be common not only during the event,=20
but in the days in wake of the storm due to prolonged sub-freezing=20 temperatures that cause persistent re-freezing on all untreated=20
surfaces. The Key Messages for the Extreme Cold are linked below=20
(Key Message 1).

Farther east, freezing rain will reach southern VA, the DelMarVa
Peninsula, and as far north as southern NJ. The southern VA
Piedmont, including the Richmond metro area, have moderate chances
(40-60%) for over one-half inch of ice. The WSSI depicts Major=20
Impacts from Richmond on south along I-95 into NC, while Moderate=20
Impacts (hazardous travel conditions) are anticipated as far north=20
as the northern DelMarVa Peninsula and into the Lower Delaware=20
Valley. While most areas farther north towards the Lower Delaware=20
Valley and southern NJ should largely remain sleet, it may=20
transition to freezing rain for a brief time by Sunday evening. WPC probabilities show low-to-moderate chances (30-50%) for over one-=20
tench of an inch of ice accumulations Sunday evening.


Key Messages for this system are linked below (Key Message 2)


Mullinax




...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!8yFFARuqbgrlMXfpwPGS4uJRxeJOXQOZNw6H1nZpRTRha= rrS6kEy-awMjMQhdY74aJIFWgelYkKRsYNo7so9y2A1flY$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!8yFFARuqbgrlMXfpwPGS4uJRxeJOXQOZNw6H1nZpRTRha= rrS6kEy-awMjMQhdY74aJIFWgelYkKRsYNo7so9tj5CnIA$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!8yFFARuqbgrlMXfpwPGS4uJRxeJOXQOZNw6H1nZpRTRha= rrS6kEy-awMjMQhdY74aJIFWgelYkKRsYNo7so9VdC50ig$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/105)

FOUS11 KWBC 251820
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
120 PM EST Sun Jan 25 2026

Valid 00Z Mon Jan 26 2026 - 00Z Thu Jan 29 2026


...Mid-Atlantic and Northeast...
Days 1-2...

The expansive winter storm will wind down across the Central
Plains and Mid-South today, but significant impacts will persist
across the Ohio Valley, Mid-Atlantic, and Northeast tonight and
Monday.

This morning, the GOES-E water vapor imagery tells the take, with
an impressive plume of moisture stretching from Texas into southern
Canada, with a clear baroclinic leaf expanding over the TN/OH
Valleys. The upper low is spinning over TX and this will lift
northward into the Ohio Valley today, while secondary low pressure
development occurs off the Mid-Atlantic coast this afternoon. This
secondary low pressure will become dominant and strengthen as it
tracks south of New England, with the most significant winter
weather and impacts shifting into New England tonight and Monday.
The trailing upper trough will move across the Great Lakes Monday,
helping to drive an inverted trough back across New England even as
the primary low departs, and light although the heaviest snow
should end Monday night, light snow may persist in this area into
Tuesday morning.=20

This evolution will result in impressive additional snow amounts
(after 00Z this evening) from the higher terrain of WV/PA northeast
through Upstate NY and all of New England. The heaviest snowfall is
expected across Upstate NY and New England where WPC probabilities
indicate a high risk (>90%) for at least 8 inches, with 12-18"
possible (30-50% chance) for the Greens, Whites, and coastal SW=20
Maine/far northern MA thanks to a coastal front evolution. Snowfall
rates will be extreme at times, potentially reaching 2-3"/hr as=20
progged by the WPC prototype snowband tool due to strong WAA=20
overlapping fgen which may result in CSI/CI (and possible=20
thundersnow). The intense WAA in the 850-700mb will drive a warm=20
nose above 0C as far north as coastal CT/RI/Cape Cod, so some=20
transition to sleet is likely, but otherwise a very cold airmass=20
will allow SLRs to be above climo (but dropping during the event)=20
which will help that efficient snow growth. The DGZ is quite=20
elevated, so the best ascent will not cross-hatch into the snow=20
growth region in most areas, but nevertheless, robust moisture on=20
IVT exceeding the 90th percentile will wring out to this heavy=20
snow, and it is possible some 48-hr total snowfall will reach more=20
than 2 feet in parts of New England, with widespread 6-12" covering
most of the Mid-Atlantic, Ohio Valley, and rest of the Northeast=20
before this event winds down.

Although most of the accumulation will occur by 12Z Monday, the
aforementioned inverted trough linking back to the upper low may
allow for wrap-around snowfall to linger much of Monday and into
Monday night adding a few more inches of cold fluffy snow to the
area, especially New England and Upstate NY. WSSI-P indicates
continues high probabilities (>80%) for major impacts, and the I-95
corridor between NYC and Portland, ME will be treacherous through
Monday.

Farther south, freezing rain will continue for parts of the Mid-
Atlantic, especially northern NC, southeast VA, and potentially
along the I-95 corridor as far north as NYC. While additional
freezing rain amounts are expected to be modest as precip begins to
wind down (WPC probabilities suggest a 50-70% chance of at least
0.1" of ice), this will be on top of prior icing to enhance impacts
including treacherous travel and power outages. With extremely cold temperatures likely after this storm persisting for many days, any
power outages will become a life-threatening situation for parts of
the Mid-Atlantic states.


...Great Lakes...
Days 1-3...

Broad cyclonic flow will persist across the east, and multiple
embedded shortwaves will ride through this trough out of Canada,
each one acting to reinforce cold advection (CAA) across the Great
Lakes to support rounds of lake effect snow (LES). While GLERL
indicates that water temperatures are cooling, Lake Erie is
entirely ice covered, and with the very cold temperatures this week
continuing, additional ice cover is expected. However, there
should still be sufficient instability and moisture to support LES
each day through the forecast period. LES is not expected to be
extremely intense, although will be efficient downstream of Lake
Ontario towards the Tug Hill Plateau at times, and it is this area
that is expected to receive the heaviest LES. WPC probabilities for
all 3 days indicate a high chance (>70%) for at least 8 inches east
of Lake Ontario, with lower probabilities for 8+ inches (10-30%
chance) southeast of Lake Michigan and across the eastern U.P. on
the south shore of Lake Superior.

Weiss



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!5X0xN7MdHtpiv0Oq5XxTtzmHSf-mjyyl5Z8e4q_9Z6UZb= c44QpuSi4xTywscDvjJby3zed3keoBg7ZLpxNDxroebvd4$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!5X0xN7MdHtpiv0Oq5XxTtzmHSf-mjyyl5Z8e4q_9Z6UZb= c44QpuSi4xTywscDvjJby3zed3keoBg7ZLpxNDxHkG_Cm8$=20



$$

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FOUS11 KWBC 260707
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
207 AM EST Mon Jan 26 2026

Valid 12Z Mon Jan 26 2026 - 12Z Thu Jan 29 2026


...New England...
Day 1...

The major winter storm that swept over the Nation the last few
days will continue to gradually exit the Northeast today, with
lingering additional snowfall across parts of New England. By the
start of the forecast period (12z Mon), the primary surface low
will be sliding east into the open Atlantic and only provide for
some favorable ocean-enhanced snow from the south coast of ME to
eastern MA. Otherwise, mostly light to moderate snow will be
associated with a weakening 850mb low tracking across northern New
England. Additional snowfall amounts through tonight are expected
to range from 3-5", with the highest probabilities (50-80%) for
greater than 4" extending from the northern coast of MA to eastern
ME. Storm total snowfall amounts from Sunday through the D1 period
are expected to exceed 20" across parts of New England.


...Great Lakes...
Days 1-3...

Broad cyclonic flow will persist across the east, and multiple
embedded shortwaves will ride through this trough out of Canada,
each one acting to reinforce cold advection (CAA) across the Great
Lakes to support rounds of lake effect snow (LES). While GLERL
indicates that water temperatures are cooling, Lake Erie is
entirely ice covered, and with the very cold temperatures this week
continuing, additional ice cover is expected. However, there
should still be sufficient instability and moisture to support LES
each day through the forecast period. LES is not expected to be
extremely intense, although will be efficient downstream of Lake
Ontario towards the Tug Hill Plateau at times, and it is this area
that is expected to receive the heaviest LES. WPC probabilities for
all 3 days indicate a high chance (>80%) for at least 12 inches
east of Lake Ontario, with lower probabilities for 8+ inches
(30-60% chance) east of Lake Michigan and across the eastern U.P.
on the south shore of Lake Superior.


Snell



$$

= = =
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FOUS11 KWBC 262022
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
322 PM EST Mon Jan 26 2026

Valid 00Z Tue Jan 27 2026 - 00Z Fri Jan 30 2026


...New England...
Day 1...

The final bands of the major winter storm shift east from New
England this evening. A couple additional inches are possible after
00Z over much of Maine down through the Mass coast.


...Great Lakes...
Days 1-3...

Broad cyclonic flow and trough passages persist across the Great
Lakes as low pressure over Hudson Bay shifts south over Ontario
through Thursday. These will produce rounds of lake effect snow=20
(LES) particularly starting Tuesday behind a notable upper trough
passage. According to GLERL, Lake Erie is essentially ice=20
covered, so available moisture will be limited there while Lakes=20
Superior and Ontario remain largely. Westerly flow allows Day 2/3=20
PWPF for >6" are over 50% in the Tug Hill and just Day 2 for the
eastern U.P. of Michigan.


...Cascades...
Days 2/3...

The next trough axis shunts the powerful ridge east Tuesday night
with precip over the WA Cascades then through Thursday. Snow levels
rise from 4000 to 5000ft over the WA Cascades Wednesday through
Thursday. PWPF for >6" is 40-70% above the snow level (above pass
level) by Thursday.


The probability for significant icing is less than 10 percent.



Jackson




...Extreme Cold Key Messages are linked below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!-0TZxpay_jM8Z4Q34rmMmud52o6t8jkHOE9b3VqfOemR-= ZzRDBrxLmQXLRJn74txeFUITeYsrY6M3nwWigr62iJQsj4$=20



$$

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FOUS11 KWBC 270733
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
233 AM EST Tue Jan 27 2026

Valid 12Z Tue Jan 27 2026 - 12Z Fri Jan 30 2026


...Great Lakes...
Days 1-3...

Broad cyclonic flow and trough passages persist across the Great
Lakes as low pressure over Hudson Bay shifts south over Ontario
through Thursday. These will produce rounds of lake effect snow=20
(LES) beginning today behind a notable upper trough passage. 850mb
temperatures will remain quite cold during this period, with
temperatures around -18 to -24C, and below the 10th climatological
percentile. According to GLERL, Lake Erie is essentially ice=20
covered, so available moisture will be limited there while Lakes=20
Superior and Ontario remain largely open. Westerly flow will
continue across the Lower Great Lakes through Thursday night, with
northerly flow more likely on Day 3 across the Upper Great Lakes,
This allows Days 1-3 PWPF for >8" over 50% in the Tug Hill and for
the eastern U.P. of Michigan. The heaviest snowfall is no doubt
most likely downwind of Lake Ontario and the Tug Hill, where 50-60% probabilities for >18" reach the shoreline of Oswego county.


...Cascades...
Days 2/3...

The next trough axis to near the Pacific Northwest shunts the=20
powerful western ridge eastward Tuesday night, with precip over=20
the WA Cascades then through Thursday. Snow levels rise from 4000=20
to 5000ft over the WA Cascades Wednesday through Thursday. PWPF for

6" is 40-70% above the snow level (above pass level) by Thursday.

The probability for significant icing is less than 10 percent.



Snell





...Extreme Cold Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!8NunqgJMY9ONsq94cDZxgfNTy_qFZpb-PYrxM2rTB5EIS= h2M4WxUege40SO-B-z28uH25Ynjwag2vrjv-7YR7oHbKF4$=20



$$

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FOUS11 KWBC 271931
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
231 PM EST Tue Jan 27 2026

Valid 00Z Wed Jan 28 2026 - 00Z Sat Jan 31 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is essentially ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue through Wednesday before the approach
of a sharp 500mb shortwave pivots through and shifts winds more out
of the N-NNW by Thursday. Northerly flow continues Friday as high
pressure builds in over the Northern Plains. 72-hour WPC
probabilities depict high chances (>70%) for snowfall totals >4"
over the northern tier of the Michigan U.P. and down wind of Lake=20
Ontario to the south of an over the Tug Hill. The area with the=20
best odds of seeing over a foot of snow over the next few days are=20
near the Oswego, NY area where WPC probabilities for over a foot of
snow are in the moderate range of probabilities (40-60%).=20


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is high (>70%) around Stevens
Pass, but lighter accumulations around Snoqualmie are anticipated
at this moment given the higher snow levels.

...Northern & Central Plains...
Days 2-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Snow is not
expected to be overly heavy, although the Black Hills through
orographic lifting may be able to see snowfall amounts surpass 6".
This is supported in WPC probabilities which show moderate-to-high
chances (50-70%) for >4" of snow in the Black Hills, and low
chances (10-30%) in their peaks for >8". Elsewhere, from eastern MT
on south and east through the Missouri River Valley, most snowfall accumulations are likely to range between 1-3". Some hazardous
travel is possible, especially where roads temperatures are at or
below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 3-3.5...

...Confidence In Impactful Snowfall Increasing For the Southern=20
Appalachians and Southern Mid-Atlantic...

To say there remains a large amount of model spread in the
potential winter storm beyond Day 3 would be an understatement. In
the past 24 hours, ensemble guidance have flipped camps to where
the GEFS are the snowier members, CMCE are more in the middle, and
the EC-EPS are trending less snowy. It is worth noting that AI=20
ensemble membership are not as snowy as the GEFS, but show a little
more snow than the EC-EPS, making this an interesting test in how=20
the AI ensemble membership performs.=20

Regarding the setup-- WPC Cluster Analysis shows this potential=20
winter storm comes down to several factors: 1) strength of the=20
emerging Great Lakes shortwave trough. 2) speed of the shortwave=20
trough. 3) tilt/amplitude of the shortwave trough as it tracks=20
east. 4) Confluence strength near Nova Scotia. They all work=20
together in an intricate dance that makes for difficulties in=20
modeling. A stronger/slower shortwave can buy time for confluence=20
over New England and Nova Scotia to weaken, giving the shortwave=20
more time to amplify, and allow for closer storm tracks to the=20
coast that bring heavy snow as far west as the I-95 corridor (some=20
GEFS members and some CMCE members). Where the shortwave is=20
stronger but progressive, heavier snowfall occurs but largely=20
closer to the coast and as far west as the NC Piedmont (CMCE=20
members, UK ensembles, split EC/GEFS members). If the shortwave=20
trough is more progressive and cannot separate itself from the=20
larger TPV to the east there is less amplification, it results in=20
a flatter and more positively/tilted shortwave trough, and thus the=20
storm remains largely out at sea (EPS, EC-AIFS ensembles, some=20
GEFS/CMCE members). It is worth noting that, while the EC-AIFS has=20
largely performed well inside of 5 days much of the winter season,=20
the EC-AIFS and ECMWF did suppress the track of the most recent=20
winter storm too much ~4-5 days out before correcting northward=20
inside of 72 hours out.

This setup is highly timing dependent; from the primary shortwave
trough currently east of Hudson Bay, to the interaction/spacing of
the 500mb cyclonic gyres in southeast Canada and south of Iceland
that promote the confluence ahead of the potential storm, to the=20
incoming Pacific shortwaves that track into western Canada and
adjust the strength/position of the western North America ridge.=20
There remain a host of embedded shortwaves that will work together=20
to create a complex storm evolution off the East Coast. Whatever=20
the current model solutions show beyond 72 hours out is unlikely to
be the final product. Expect additional model changes in the=20
coming days. If there is one thing that has increased in confidence
in the past 24 hours, it is the opportunity for coastal flooding=20
and beach erosion along the Mid-Atlantic coast. Please refer to our
"What We know, What We Don't Know" social media post for=20
additional information.

The one thing they do agree on is this upper trough tracks through
the OH Valley Friday afternoon with sufficient PVA and 850-500mb=20
mean layer moisture to support snow from central KY to the southern Appalachians through Friday evening. WPC probabilities do
show increasing chances for at least minor accumulations >2" over
KY and northeast TN, while there are low-chances (10-30%) for
snowfall totals >4" through early Saturday morning in the TN/NC Smokeys
and Blue Ridge of NC. Residents and those traveling to the=20
Carolinas on north up the East Coast will want to continue=20
following the forecasts from WPC and your local NWS WFO for the=20
latest regarding this potential winter storm.=20


The probability for significant icing is less than 10 percent.


Mullinax




...Extreme Cold Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!6VI14otitwAAstNrC60qAGwJSrOE6Zf0oLu0MtZRucHys= 6sfDSsnz6A0nRg5hdjsoJ-6sT4HYazaHiiRfGLVWtSFuMg$=20



$$

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FOUS11 KWBC 272009
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
309 PM EST Tue Jan 27 2026

Valid 00Z Wed Jan 28 2026 - 00Z Sat Jan 31 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is essentially ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue through Wednesday before the approach
of a sharp 500mb shortwave pivots through and shifts winds more out
of the N-NNW by Thursday. Northerly flow continues Friday as high
pressure builds in over the Northern Plains. 72-hour WPC
probabilities depict high chances (>70%) for snowfall totals >4"
over the northern tier of the Michigan U.P. and down wind of Lake=20
Ontario to the south of an over the Tug Hill. The area with the=20
best odds of seeing over a foot of snow over the next few days are=20
near the Oswego, NY area where WPC probabilities for over a foot of
snow are in the moderate range of probabilities (40-60%).=20


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is high (>70%) around Stevens
Pass, but lighter accumulations around Snoqualmie are anticipated
at this moment given the higher snow levels.

...Northern & Central Plains...
Days 2-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Snow is not
expected to be overly heavy, although the Black Hills through
orographic lifting may be able to see snowfall amounts surpass 6".
This is supported in WPC probabilities which show moderate-to-high
chances (50-70%) for >4" of snow in the Black Hills, and low
chances (10-30%) in their peaks for >8". Elsewhere, from eastern MT
on south and east through the Missouri River Valley, most snowfall accumulations are likely to range between 1-3". Some hazardous
travel is possible, especially where roads temperatures are at or
below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 3-3.5...

...Confidence In Impactful Snowfall Increasing For the Southern=20
Appalachians and Southern Mid-Atlantic...

To say there remains a large amount of model spread in the
potential winter storm beyond Day 3 would be an understatement. In
the past 24 hours, ensemble guidance have flipped camps to where
the GEFS are the snowier members, CMCE are more in the middle, and
the EC-EPS are trending less snowy. It is worth noting that AI=20
ensemble membership are not as snowy as the GEFS, but show a little
more snow than the EC-EPS, making this an interesting test in how=20
the AI ensemble membership performs.=20

Regarding the setup-- WPC Cluster Analysis shows this potential=20
winter storm comes down to several factors: 1) strength of the=20
emerging Great Lakes shortwave trough. 2) speed of the shortwave=20
trough. 3) tilt/amplitude of the shortwave trough as it tracks=20
east. 4) Confluence strength near Nova Scotia. They all work=20
together in an intricate dance that makes for difficulties in=20
modeling. A stronger/slower shortwave can buy time for confluence=20
over New England and Nova Scotia to weaken, giving the shortwave=20
more time to amplify, and allow for closer storm tracks to the=20
coast that bring heavy snow as far west as the I-95 corridor (some=20
GEFS members and some CMCE members). Where the shortwave is=20
stronger but progressive, heavier snowfall occurs but largely=20
closer to the coast and as far west as the NC Piedmont (CMCE=20
members, UK ensembles, split EC/GEFS members). If the shortwave=20
trough is more progressive and cannot separate itself from the=20
larger TPV to the east there is less amplification, it results in=20
a flatter and more positively/tilted shortwave trough, and thus the storm remains largely out at sea (EPS, EC-AIFS ensembles, some GEFS/CMCE
members). It is worth noting that, while the EC-AIFS has largely=20
performed well inside of 5 days much of the winter season, the EC-=20
AIFS and ECMWF did suppress the track of the most recent winter=20
storm too much ~4-5 days out before correcting northward inside of=20
72 hours out.

This setup is highly timing dependent; from the primary shortwave
trough currently east of Hudson Bay, to the interaction/spacing of
the 500mb cyclonic gyres in southeast Canada and south of Iceland
that promote the confluence ahead of the potential storm, to the=20
incoming Pacific shortwaves that track into western Canada and
adjust the strength/position of the western North America ridge.=20
There remain a host of embedded shortwaves that will work together=20
to create a complex storm evolution off the East Coast. Whatever=20
the current model solutions show beyond 72 hours out is unlikely to
be the final product. Expect additional model changes in the=20
coming days. If there is one thing that has increased in confidence
in the past 24 hours, it is the opportunity for coastal flooding=20
and beach erosion along the Mid-Atlantic coast. Please refer to our
"What We know, What We Don't Know" social media post for=20
additional information.

The one thing they do agree on is this upper trough tracks through
the OH Valley Friday afternoon with sufficient PVA and 850-500mb=20
mean layer moisture to support snow from central KY to the southern Appalachians through Friday evening. WPC probabilities do
show increasing chances for at least minor accumulations >2" over
KY and northeast TN, while there are low-chances (10-30%) for
snowfall totals >4" through early Saturday morning in the TN/NC
Smokeys and Blue Ridge of NC. Residents and those traveling to the
Carolinas on north up the East Coast will want to continue=20
following the forecasts from WPC and your local NWS WFO for the=20
latest regarding this potential winter storm.=20


The probability for significant icing is less than 10 percent.


Mullinax





...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!54SB-pOI55Au96P5L94fHwqMmZ5LkWpzYAasipw8QCoDB= HpKat7rnUR9CGCuvaNDYBiVEtFlpNZAFxNTxzAKGVc0XKY$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
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FOUS11 KWBC 272012
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
312 PM EST Tue Jan 27 2026

Valid 00Z Wed Jan 28 2026 - 00Z Sat Jan 31 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is essentially ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue through Wednesday before the approach
of a sharp 500mb shortwave pivots through and shifts winds more out
of the N-NNW by Thursday. Northerly flow continues Friday as high
pressure builds in over the Northern Plains. 72-hour WPC
probabilities depict high chances (>70%) for snowfall totals >4"
over the northern tier of the Michigan U.P. and down wind of Lake=20
Ontario to the south of an over the Tug Hill. The area with the=20
best odds of seeing over a foot of snow over the next few days are=20
near the Oswego, NY area where WPC probabilities for over a foot of
snow are in the moderate range of probabilities (40-60%).=20


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is high (>70%) around Stevens
Pass, but lighter accumulations around Snoqualmie are anticipated
at this moment given the higher snow levels.

...Northern & Central Plains...
Days 2-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Snow is not
expected to be overly heavy, although the Black Hills through
orographic lifting may be able to see snowfall amounts surpass 6".
This is supported in WPC probabilities which show moderate-to-high
chances (50-70%) for >4" of snow in the Black Hills, and low
chances (10-30%) in their peaks for >8". Elsewhere, from eastern MT
on south and east through the Missouri River Valley, most snowfall accumulations are likely to range between 1-3". Some hazardous
travel is possible, especially where roads temperatures are at or
below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 3-3.5...

...Confidence In Impactful Snowfall Increasing For the Southern=20
Appalachians and Southern Mid-Atlantic...

To say there remains a large amount of model spread in the
potential winter storm beyond Day 3 would be an understatement. In
the past 24 hours, ensemble guidance have flipped camps to where
the GEFS are the snowier members, CMCE are more in the middle, and
the EC-EPS are trending less snowy. It is worth noting that AI=20
ensemble membership are not as snowy as the GEFS, but show a little
more snow than the EC-EPS, making this an interesting test in how=20
the AI ensemble membership performs.=20

Regarding the setup-- WPC Cluster Analysis shows this potential=20
winter storm comes down to several factors: 1) strength of the=20
emerging Great Lakes shortwave trough. 2) speed of the shortwave=20
trough. 3) tilt/amplitude of the shortwave trough as it tracks=20
east. 4) Confluence strength near Nova Scotia. They all work=20
together in an intricate dance that makes for difficulties in=20
modeling. A stronger/slower shortwave can buy time for confluence=20
over New England and Nova Scotia to weaken, giving the shortwave=20
more time to amplify, and allow for closer storm tracks to the=20
coast that bring heavy snow as far west as the I-95 corridor (some=20
GEFS members and some CMCE members). Where the shortwave is=20
stronger but progressive, heavier snowfall occurs but largely=20
closer to the coast and as far west as the NC Piedmont (CMCE=20
members, UK ensembles, split EC/GEFS members). If the shortwave=20
trough is more progressive and cannot separate itself from the=20
larger TPV to the east there is less amplification, it results in=20
a flatter and more positively/tilted shortwave trough, and thus the
storm remains largely out at sea (EPS, EC-AIFS ensembles, some=20
GEFS/CMCE members). It is worth noting that, while the EC-AIFS has=20
largely performed well inside of 5 days much of the winter season,=20
the EC- AIFS and ECMWF did suppress the track of the most recent=20
winter storm too much ~4-5 days out before correcting northward=20
inside of 72 hours out.

This setup is highly timing dependent; from the primary shortwave
trough currently east of Hudson Bay, to the interaction/spacing of
the 500mb cyclonic gyres in southeast Canada and south of Iceland
that promote the confluence ahead of the potential storm, to the=20
incoming Pacific shortwaves that track into western Canada and
adjust the strength/position of the western North America ridge.=20
There remain a host of embedded shortwaves that will work together=20
to create a complex storm evolution off the East Coast. Whatever=20
the current model solutions show beyond 72 hours out is unlikely to
be the final product. Expect additional model changes in the=20
coming days. If there is one thing that has increased in confidence
in the past 24 hours, it is the opportunity for coastal flooding=20
and beach erosion along the Mid-Atlantic coast. Please refer to our
"What We know, What We Don't Know" social media post for=20
additional information.

The one thing they do agree on is this upper trough tracks through
the OH Valley Friday afternoon with sufficient PVA and 850-500mb=20
mean layer moisture to support snow from central KY to the southern Appalachians through Friday evening. WPC probabilities do
show increasing chances for at least minor accumulations >2" over
KY and northeast TN, while there are low-chances (10-30%) for
snowfall totals >4" through early Saturday morning in the TN/NC
Smokeys and Blue Ridge of NC. Residents and those traveling to the
Carolinas on north up the East Coast will want to continue=20
following the forecasts from WPC and your local NWS WFO for the=20
latest regarding this potential winter storm.=20


The probability for significant icing is less than 10 percent.


Mullinax






...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!6n-iHJKs776ZdQQmter1T3bY9tYWwGaL_csVXzv1NZMbv= Z1KeGyQSUWbB1TKYcgb1-m6K7MWiSPxJKNPHtV9eyKYDFI$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
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FOUS11 KWBC 280759
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
259 AM EST Wed Jan 28 2026

Valid 12Z Wed Jan 28 2026 - 12Z Sat Jan 31 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is essentially ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue today before the approach of a sharp
500mb shortwave pivots through and shifts winds more out of the=20
N-NNW by Thursday. Northerly flow continues Friday as high pressure
builds in over the Northern Plains. This northerly flow supports
the most likely area of heavy snow on Day 3 to be down wind of Lake
Michigan, potentially into the Chicago metro. 72-hour WPC=20
probabilities depict high chances (>70%) for snowfall totals >8"=20
over the eastern shores of Lake Superior in the Michigan U.P. and=20
down wind of Lake Ontario to the south of an over the Tug Hill. The
area with the best odds of seeing over a foot of additional snow=20
(most on Day 1) over the next few days are near the Oswego, NY area
where WPC probabilities for over a foot of snow are 10-20%. Day 3
probabilities down wind of Lake Michigan current depict moderate
probabilities 40-50% for at least 4" across the southwest shores of
Lake Michigan.


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is moderate (40-70%) around=20
Stevens Pass, but lighter accumulations around Snoqualmie are=20
anticipated at this moment given the higher snow levels.

...Northern & Central Plains...
Days 2-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Snow is not
expected to be overly heavy, although the Black Hills through
orographic lifting may be able to see snowfall amounts surpass 6".
This is supported in WPC probabilities which show moderate-to-high
chances (50-70%) for >4" of snow in the Black Hills, and low
chances (10-30%) in their peaks for >8". Elsewhere, from eastern MT
on south and east through the Missouri River Valley, most snowfall accumulations are likely to range between 1-3". Some hazardous
travel is possible, especially where roads temperatures are at or
below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 3...

...Confidence In Impactful Snowfall Increasing For the Southern=20
Appalachians and Southern Mid-Atlantic; Key Messages are linked at
the bottom of the discussion...

To say there remains a large amount of model spread in the
potential winter storm beyond Day 3 would be an understatement. In
the past 36-24 hours, ensemble guidance have flipped camps to=20
where the GEFS are the snowier members, CMCE are more in the=20
middle, and the EC-EPS are less snowy. It is worth noting that AI=20
ensemble membership are not as snowy as the GEFS, but show a little
more snow than the EC-EPS, making this an interesting test in how=20
the AI ensemble membership performs. However, within this overall
"cloud" of uncertainty, guidance is beginning to hone in on higher
chances for impactful snowfall across the Carolinas and southern
Virginia by the end of the Day 3 timeframe.

Regarding the setup-- WPC Cluster Analysis shows this potential=20
winter storm comes down to several factors: 1) strength of the=20
emerging Great Lakes shortwave trough. 2) speed of the shortwave=20
trough. 3) tilt/amplitude of the shortwave trough as it tracks=20
east. 4) Confluence strength near Nova Scotia. They all work=20
together in an intricate dance that makes for difficulties in=20
modeling. A stronger/slower shortwave can buy time for confluence=20
over New England and Nova Scotia to weaken, giving the shortwave=20
more time to amplify, and allow for closer storm tracks to the=20
coast that bring heavy snow as far west as the I-95 corridor (some=20
GEFS members and some CMCE members). Where the shortwave is=20
stronger but progressive, heavier snowfall occurs but largely=20
closer to the coast and as far west as the NC Piedmont (CMCE=20
members, UK ensembles, split EC/GEFS members). If the shortwave=20
trough is more progressive and cannot separate itself from the=20
larger TPV to the east there is less amplification, it results in=20
a flatter and more positively/tilted shortwave trough, and thus the
storm remains largely out at sea (EPS, EC-AIFS ensembles, some=20
GEFS/CMCE members). It is worth noting that, while the EC-AIFS has=20
largely performed well inside of 5 days much of the winter season,=20
the EC- AIFS and ECMWF did suppress the track of the most recent=20
winter storm too much ~4-5 days out before correcting northward=20
inside of 72 hours out.

In terms of storm analogs, this upper level setup and TPV=20
interaction does not appear like a common scenario to get a deep=20
upper low rapidly deepening near the Southeast/Mid- Atlantic. Most=20
analog matches seem to get towards the closed upper low in=20
different ways or suppress the system altogether leaving little in=20
terms of precipitation. However, the 12z Tuesday CIPS Analogs
(GFS-based) highlighted the significant winter storm of March 1980
as an interesting top match. This storm produced very heavy=20
snowfall across VA and eastern NC and can simply show the ceiling=20
this type of setup can have. Like what was previously mentioned,=20
other limited analogs are suppressed and show the very low floor=20
that is still possible. All ensemble systems GEFS/CMCE/EPS/EC-
AIFS/AIGEFS show this large spread as well.

Back to the current forecast. This setup is highly timing=20
dependent; from the primary shortwave trough currently east of=20
Hudson Bay, to the interaction/spacing of the 500mb cyclonic gyres=20
in southeast Canada and south of Iceland that promote the=20
confluence ahead of the potential storm, to the incoming Pacific=20
shortwaves that track into western Canada and adjust the=20
strength/position of the western North America ridge. There remain=20
a host of embedded shortwaves that will work together to create a=20
complex storm evolution off the East Coast. Whatever the current=20
model solutions show beyond 72 hours out is unlikely to be the=20
final product. Expect additional model changes in the coming days.=20
If there is an additional aspect to this storm that has increased=20
in confidence in the past 24 hours, it is the opportunity for=20
coastal flooding and beach erosion along the Mid-Atlantic coast.

The one thing they do agree on is this upper trough tracks through
the OH Valley Friday afternoon with sufficient PVA and 850-500mb=20
mean layer moisture to support snow from central KY to the southern Appalachians through Friday night. Then, the closing off of a 850mb
low seems plausible across the southern Appalachians Saturday=20
morning, which should help increase lift into the Carolina=20
Piedmont. WPC probabilities do show increasing chances for at least
minor accumulations >4" over eastern KY and northeast TN, while=20
there are low- chances (10-30%) for snowfall totals >4" through=20
early Saturday morning in the TN/NC Smokeys and Blue Ridge of NC.=20 Probabilities then begin to increase to 30-50% across central NC by
12z Saturday. Most snowfall associated with this system is=20
expected to occur after 12z Saturday, so be sure to check back for=20
the latest forecast as it enters the short range over the next few=20
days. Residents and those traveling to the Carolinas on north up=20
the East Coast will want to continue following the forecasts from=20
WPC and your local NWS WFO for the latest regarding this potential=20
winter storm.



The probability for significant icing is less than 10 percent.


Snell/Mullinax





...Extreme Cold (1) & Winter Storm (2) Key Messages are in effect.
Please see current Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!77Xu4C4_ejyNPuXJ8gEnnObVKlTXBwG2suWpfLuKOVzPG= BINbP5K5P9TIQ5cCqP2wLS3M1N8_NCpSzZOgD1PInZ4pUQ$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!77Xu4C4_ejyNPuXJ8gEnnObVKlTXBwG2suWpfLuKOVzPG= BINbP5K5P9TIQ5cCqP2wLS3M1N8_NCpSzZOgD1PtfsLqMU$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/105)

FOUS11 KWBC 280807
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
307 AM EST Wed Jan 28 2026

Valid 12Z Wed Jan 28 2026 - 12Z Sat Jan 31 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is essentially ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue today before the approach of a sharp
500mb shortwave pivots through and shifts winds more out of the=20
N-NNW by Thursday. Northerly flow continues Friday as high pressure
builds in over the Northern Plains. This northerly flow supports
the most likely area of heavy snow on Day 3 to be down wind of Lake
Michigan, potentially into the Chicago metro. 72-hour WPC=20
probabilities depict high chances (>70%) for snowfall totals >8"=20
over the eastern shores of Lake Superior in the Michigan U.P. and=20
down wind of Lake Ontario to the south of an over the Tug Hill. The
area with the best odds of seeing over a foot of additional snow=20
(most on Day 1) over the next few days are near the Oswego, NY area
where WPC probabilities for over a foot of snow are 10-20%. Day 3
probabilities down wind of Lake Michigan current depict moderate
probabilities 40-50% for at least 4" across the southwest shores of
Lake Michigan.


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is moderate (40-70%) around=20
Stevens Pass, but lighter accumulations around Snoqualmie are=20
anticipated at this moment given the higher snow levels.

...Northern & Central Plains...
Days 2-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Snow is not
expected to be overly heavy, although the Black Hills through
orographic lifting may be able to see snowfall amounts surpass 6".
This is supported in WPC probabilities which show moderate-to-high
chances (50-70%) for >4" of snow in the Black Hills, and low
chances (10-30%) in their peaks for >8". Elsewhere, from eastern MT
on south and east through the Missouri River Valley, most snowfall accumulations are likely to range between 1-3". Some hazardous
travel is possible, especially where roads temperatures are at or
below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 3...

...Confidence In Impactful Snowfall Increasing For the Southern=20
Appalachians and Southern Mid-Atlantic; Key Messages are linked at
the bottom of the discussion...

To say there remains a large amount of model spread in the
potential winter storm beyond Day 3 would be an understatement. In
the past 36-24 hours, ensemble guidance have flipped camps to=20
where the GEFS are the snowier members, CMCE are more in the=20
middle, and the EC-EPS are less snowy. It is worth noting that AI=20
ensemble membership are not as snowy as the GEFS, but show a little
more snow than the EC-EPS, making this an interesting test in how=20
the AI ensemble membership performs. However, within this overall
"cloud" of uncertainty, guidance is beginning to hone in on higher
chances for impactful snowfall across the Carolinas and southern
Virginia by the end of the Day 3 timeframe.

Regarding the setup-- WPC Cluster Analysis shows this potential=20
winter storm comes down to several factors: 1) strength of the=20
emerging Great Lakes shortwave trough. 2) speed of the shortwave=20
trough. 3) tilt/amplitude of the shortwave trough as it tracks=20
east. 4) Confluence strength near Nova Scotia. They all work=20
together in an intricate dance that makes for difficulties in=20
modeling. A stronger/slower shortwave can buy time for confluence=20
over New England and Nova Scotia to weaken, giving the shortwave=20
more time to amplify, and allow for closer storm tracks to the=20
coast that bring heavy snow as far west as the I-95 corridor (some=20
GEFS members and some CMCE members). Where the shortwave is=20
stronger but progressive, heavier snowfall occurs but largely=20
closer to the coast and as far west as the NC Piedmont (CMCE=20
members, UK ensembles, split EC/GEFS members). If the shortwave=20
trough is more progressive and cannot separate itself from the=20
larger TPV to the east there is less amplification, it results in=20
a flatter and more positively/tilted shortwave trough, and thus the
storm remains largely out at sea (EPS, EC-AIFS ensembles, some=20
GEFS/CMCE members). It is worth noting that, while the EC-AIFS has=20
largely performed well inside of 5 days much of the winter season,=20
the EC- AIFS and ECMWF did suppress the track of the most recent=20
winter storm too much ~4-5 days out before correcting northward=20
inside of 72 hours out.

In terms of storm analogs, this upper level setup and TPV=20
interaction does not appear like a common scenario to get a deep=20
upper low rapidly strengthening near the Southeast/Mid- Atlantic.=20
Most analog matches seem to get towards the closed upper low in=20
different ways or suppress the system altogether leaving little in=20
terms of precipitation. However, the 12z Tuesday CIPS Analogs (GFS-
based) highlighted the significant winter storm of March 1980 as=20
an interesting top match. This storm produced very heavy snowfall=20
across VA and eastern NC and can simply show the ceiling this type=20
of setup can have. Like what was previously mentioned, other=20
limited analogs are suppressed and show the very low floor that is=20
still possible. All ensemble systems GEFS/CMCE/EPS/EC- AIFS/AIGEFS=20
show this large spread as well.

Back to the current forecast. This setup is highly timing=20
dependent; from the primary shortwave trough currently east of=20
Hudson Bay, to the interaction/spacing of the 500mb cyclonic gyres=20
in southeast Canada and south of Iceland that promote the=20
confluence ahead of the potential storm, to the incoming Pacific=20
shortwaves that track into western Canada and adjust the=20
strength/position of the western North America ridge. There remain=20
a host of embedded shortwaves that will work together to create a=20
complex storm evolution off the East Coast. Whatever the current=20
model solutions show beyond 72 hours out is unlikely to be the=20
final product. Expect additional model changes in the coming days.=20
If there is an additional aspect to this storm that has increased=20
in confidence in the past 24 hours, it is the opportunity for=20
coastal flooding and beach erosion along the Mid-Atlantic coast.

The one thing they do agree on is this upper trough tracks through
the OH Valley Friday afternoon with sufficient PVA and 850-500mb=20
mean layer moisture to support snow from central KY to the southern Appalachians through Friday night. Then, the closing off of a 850mb
low seems plausible across the southern Appalachians Saturday=20
morning, which should help increase lift into the Carolina=20
Piedmont. WPC probabilities do show increasing chances for at least
minor accumulations >4" over eastern KY and northeast TN, while=20
there are low- chances (10-30%) for snowfall totals >4" through=20
early Saturday morning in the TN/NC Smokeys and Blue Ridge of NC.=20 Probabilities then begin to increase to 30-50% across central NC by
12z Saturday. Most snowfall associated with this system is=20
expected to occur after 12z Saturday, so be sure to check back for=20
the latest forecast as it enters the short range over the next few=20
days. Residents and those traveling to the Carolinas on north up=20
the East Coast will want to continue following the forecasts from=20
WPC and your local NWS WFO for the latest regarding this potential=20
winter storm.



The probability for significant icing is less than 10 percent.


Snell/Mullinax





...Extreme Cold (1) & Winter Storm (2) Key Messages are in effect.
Please see current Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!8TANDUoTZL_uMahppCEn7lOgTUVSMGtUDbz_RXsEfHhME= ATsMx_veotJcy8MV2KCSOFvGpr4l7xjG6CeUg9vKvyvDL8$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!8TANDUoTZL_uMahppCEn7lOgTUVSMGtUDbz_RXsEfHhME= ATsMx_veotJcy8MV2KCSOFvGpr4l7xjG6CeUg9vTm6w4sc$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/105)

FOUS11 KWBC 281947
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
247 PM EST Wed Jan 28 2026

Valid 00Z Thu Jan 29 2026 - 00Z Sun Feb 01 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is effectively ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue today before the approach of a sharp
500mb shortwave passes through and shifts winds more out of the=20
north by late Thursday. Northerly flow continues Friday with=20
shifting NNE flow possible into Saturday, which could place the=20
Chicagoland area under the presence of a Lake Michigan single-=20
banded LES streamer late Friday into Saturday. 72-hour WPC=20
probabilities depict high chances (>70%) for snowfall totals >8"=20
over the eastern shores of Lake Superior in the Michigan U.P. and=20
down wind of Lake Ontario to the south of an over the Tug Hill. The
area with the best odds of seeing over a foot of additional snow=20
(most on Day 1) over the next few days are near the Oswego, NY area
where WPC probabilities for over a foot of snow are 10-20%. Day 3=20 probabilities down wind of Lake Michigan current depict moderate-=20
to-high chances (40-70%) for at least 4" along the southern shores
of Lake Michigan.


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is moderate (40-60%) around=20
Stevens Pass, but lighter accumulations around Snoqualmie are=20
anticipated at this moment given the higher snow levels.

...Northern & Central Plains...
Days 1-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Guidance is
even keying in on an area of 700mb FGEN over the Black Hills on
south into the Nebraska Sand Hills that could support moderate snow
bands Friday morning. Snow is not expected to be overly heavy,=20
although the Black Hills through orographic lifting and some=20
localized banding may be able to see snowfall amounts surpass 6".=20
This is supported in WPC probabilities which show moderate-to-high=20
chances (50-70%) for >4" of snow in the Black Hills, and low-to-=20
moderate chances (20-50%) in their peaks for >8". Elsewhere, from=20
eastern MT on south and east through the Missouri River Valley,=20
most snowfall accumulations are likely to range between 1-3". Even=20
some localized instances of freezing rain in the northern High=20
Plains on late Friday into Saturday given the favorable overrunning
from WAA at low-mid levels and sub-freezing surface temps. Some=20
hazardous travel is possible, especially where roads temperatures=20
are at or below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 2.5-3.5...

...Confidence growing for a major winter storm & heavy snowfall=20
across the southern Mid-Atlantic...

WPC cluster analysis continues to show the primary driving factors
in the development of this impending winter storm are the
strength/speed/tilt of the approaching shortwave trough in the
Great Lakes and the spacing between the trough and the TPV over
southeast Canada. The meteorology is supportive of a significant
winter storm from the southern Appalachians and Carolinas on north
and east through the VA Tidewater. Just about all ensemble=20
guidance now show the shortwave trough over the OH Valley Friday=20
evening deepening into a powerful and highly anomalous closed low=20
that tracks into the southern Appalachians Saturday evening. By the
end of this forecast period (00Z Sun) the ECMWF 500mb heights are=20 approaching record low levels over the FL Panhandle for late Jan-=20
early Feb. As the 500mb low approaches, exceptional PVA and WAA=20
over the Mid-Atlantic coast will spawn low pressure along the=20
strengthening coastal front. This aligns well across the 12Z GFS=20
and 06Z ECMWF which show increasing 700mb Q-vector convergence near
the NC Outer Banks that fosters healthy mid-level ascent. This=20
aligns favorably beneath the diffluent left-exit region of a=20

100kt 500mb jet streak located a the base of the closed 500mb low.

As the 700mb low tracks towards the Cape Fear region Saturday=20
night, the axis of heaviest snowfall will reside on the 700mb low's
northern and western flank.

Where guidance still disagrees is the progression of the storm and
its proximity to the coast. The tilt of the 500mb trough and closed
low plays a key role in this, as it maximizes vertical ascent and=20
draws moisture farther north if the system takes on a negative=20
tilt. The EC-AIFS ensemble mean has been gradually decreasing QPF=20
largely because the negative tilt takes longer to occur and there=20
is less time for the developing 850mb low to tap into moisture off
the Gulf Stream. Most guidance holds off on a negative until=20
Sunday, which is why there is a "gap" in the snowfall from northern
VA on up I-95 to the NYC metro area, but heavy snow becomes=20
possible over southeast New England by Sunday thanks to the region=20
sticking out eastward into the Atlantic. Note the 12Z GEFS, 06Z=20
EPS, and 12Z EC-AIFS ensembles are still showing changes in its=20
mean inside of 72 hours, so exact amounts and the expanse of the=20
snow shield are still likely to change. In addition, unlike the=20
last winter storm, wind will have a more profound impact up and=20
down the Eastern Seaboard. The 00Z ECMWF EFI shows wind speeds that
are topping 0.8 from the MA Capes on south along the NC Coast.=20
These anomalous winds also align with climatologically significant=20
snowfall potential along the coasts, indicating the concern for=20
blizzard conditions in affected coastal areas.=20

CIPS Analogs (GFS-based) continue to suggest this storm's=20
potential ceiling could be exceptional, particularly in the=20
Carolinas. CIPS is keying in on several past major winter storms=20
that featured similar 300mb & 500mb evolutions to what the GFS is=20
showing, just 100-200 miles farther south and east from where those
events unfolded. While the CIPS analogs are analyzing the GFS, the
differences in the GFS versus the ECMWF are not all that different
when it comes to the meteorology involved: powerful closed upper=20
low, healthy upper-level divergence over a strengthening coastal=20
front, and tapping into Atlantic moisture revolving around the=20
closed 700mb low. In summary-- ensembles are beginning to identify
the floor of this winter storm (disruptive winter storm in the=20
southern Mid-Atlantic) but based on some of the analogs, there is a
potentially more significant-ceiling that could be achieved in the
Carolinas should guidance consolidate on a slower and more intense
winter storm. Given it is 72 hours out, there remains some caution
when it comes to expected snowfall totals.

WPC probabilities through Saturday night currently show moderate-
to-high chances (50-80%) for snowfall totals >4" from the NC=20
Piedmont on east to eastern NC and southeast VA. It is worth noting
some higher end solutions are present with low-to-moderate chances
(30-50%) for snowfall totals >8" over central NC through 06Z Sunday.
The Probabilistic Winter Storm Severity Index (WSSI-P) is=20
depicting >50% chances for Moderate Impacts from the SC/GA border=20
on north and east to lower DelMarVa Peninsula. The Major Impacts=20
are >50% in the eastern Charlotte metro, the NC Piedmont right=20
along NC's I-95 corridor, and into southeast VA. These elevated
WSSI-P Major probabilities highlight the concern for a highly=20
impactful winter storm late Saturday and into Sunday for the=20
southern Mid-Atlantic with more disruptions to travel and=20
infrastructure anticipated. Residents and those traveling to the=20
Carolinas on north up the East Coast will want to continue=20
following the forecasts from WPC and your local NWS WFO for the=20
latest regarding this potential winter storm.


The probability for significant icing is less than 10 percent.


Mullinax




...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!5Cj4msK-dv0Kb7_AGDSgu7ZDdEOXNYFYPw2QvpYtmFd6N= CNtmp24XMTtrscfs6fvs4sGCn1UXXix-0GDZBAeT4q-EBM$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!5Cj4msK-dv0Kb7_AGDSgu7ZDdEOXNYFYPw2QvpYtmFd6N= CNtmp24XMTtrscfs6fvs4sGCn1UXXix-0GDZBAeMWJe7mA$=20



$$

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FOUS11 KWBC 292015
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
315 PM EST Thu Jan 29 2026

Valid 00Z Fri Jan 30 2026 - 00Z Mon Feb 02 2026


...Southern Appalachians, Mid-Atlantic, & Southern New England...=20
Days 1-3...

...A major winter storm is expected to produce heavy snowfall=20
across the southern Mid-Atlantic, blizzard conditions along the=20
Mid- Atlantic coasts, & potentially heavy snow in southern New=20
England...

Meteorological Overview...

An arctic air-mass anchored over the eastern U.S. will set the
stage for an amplifying shortwave trough over the OH Valley to
produce a major winter storm over the southern Appalachians and=20
southern Mid-Atlantic beginning Friday afternoon and continuing
into the weekend. Snow will begin as early as Friday morning=20
across the TN Valley and east to the southern/central Appalachians=20
due to low-level WAA, increasing PVA aloft, plus upslope=20
enhancement into the Appalachians. As the upper trough sharpens=20
over near the OH/MS Confluence, a robust >100kt 500mb jet streak=20
will place its divergent left-exit region over the southern Mid-=20
Atlantic and snow will envelop much of the Appalachians and=20
Piedmont of the Southeast come early Saturday morning.=20

By 12Z Saturday, most guidance is in agreement that the 500mb
shortwave takes on a more neutral tilt (oriented N-S) over the TN
Valley and becomes a closed low over GA. PVA becomes maximized=20
over the Southeast while a surface low spawns along a coastal=20
front east of the Carolinas. As the 850mb low deepens over northern
GA and heads east into SC, easterly 850mb theta-e advection will=20
direct low-level moisture around the 850mb low and support a band=20
of moderate-to-heavy snow from northern GA to central SC. Farther=20
north, the same tongue of 850mb theta-e is funneling along the=20
850mb front to the north of the 850mb low track from northern SC=20
on east through the heart of NC. This is where the deformation zone
is likely to form, pivoting over central NC and northern SC with=20
1-2"/hr snowfall rates likely. This band of heavy snow is likely to
ensue farther east into southeast VA, where 700mb FGEN is more=20
ideally placed to support strong vertical velocities within a fully
saturated DGZ. Similar to NC, look for intense bands of heavy snow
over southeast VA to form late Saturday afternoon and persist into
Saturday night. These bands of heavy snow in eastern NC and=20
southeast VA depict 700-500mb lapse rates >6.5C/km Saturday=20
afternoon and evening. It is here where not only are 2"/hr snowfall
rates achievable, but so is the likelihood for thundersnow. The
intense vertical velocities in eastern NC and southeast VA may
result in some subsidence in north-central NC and south-central VA.
Snowfall is still likely to reach warning criteria, but these
regions are potentially susceptible to lesser snowfall amounts as
they are caught between the influence of the strong upper-low to
the south, and the strengthening coastal low.

Speaking of the coastal low, along the coast VA/NC/SC coasts, not=20
only will the deformation zone of heavy snow pivot through, but the
explosive deepening of the storm east of Cape Hatteras will=20
support strong to potentially damaging wind gusts. Latest ECMWF=20
shows low pressure south of Hatteras is around 1007mb at 12Z=20
Saturday, then by 12Z Sunday is 972mb east of Hatteras, indicative=20
of rapid intensification. With strong high pressure to the west, a=20
strong isallobaric flow will develop in response, creating wind=20
gusts along the DelMarVa coast on south through the Outer Banks=20
that could approach hurricane-force at times. These coastal areas=20
overlap with the ECMWF EFI in >0.8 values for both snow and wind,=20
making these areas most susceptible to blizzard conditions. Not to=20
be ignored either, strong wind gusts atop the Smokeys and Blue=20
Ridge are likely to top 60 mph as well, resulting in possible=20
blizzard conditions in those higher elevations of the southern=20
Appalachians. Power outages are likely in some parts of the
southern Mid-Atlantic, particularly areas at risk for those
hurricane-force wind gusts along the VA/NC coast.

While there is still some uncertainty in storm track, most guidance
(including AIFS ensembles) have continued to trend lower in
snowfall amounts from northern VA on north and east along I-95 to=20
the Tri-state area. There remains a high degree of uncertainty over
southeast MA where the differences in the EPS-AIFS 75th and 25th=20
percentile snowfall outcomes south of Boston still are quite=20
striking. The locations that should still contend with periods of=20
snow are Martha's Vineyard and Nantucket given their closer=20
proximity to the snow shield.=20

Snowfall & Impacts...

WPC probabilities for the duration of the event show moderate-to-
high chances (50-80%) for snowfall totals >8" in the Blue
Ridge/Smokeys, west-central NC on east through northern SC,
southern NC, and along the Tidewater regions of VA/NC. It is
southeast VA, eastern NC, and southern NC that feature the highest
odds for snowfall totals >12" at 40-60%. Wilmington, NC has at
least a 50% chance of receiving >12" of snow. For context, dating=20
back to 1870, Wilmington, NC has only observed 3 instances where=20

12" of snowfall occurred: Feb 1896, Feb 1973, and Dec 1989.=20

The snowfall likely to occur across the Carolinas has a good=20
chance to be not just significant but historic and highly=20
disruptive, not just during the event, but for days after it is=20
long gone. WSSI shows an expansive area of Major Impacts=20
(considerable disruptions to daily life; dangerous to impossible=20
travel, widespread closures, disruptions to infrastructure) from=20
central SC (including Columbia, SC) through the eastern two-thirds=20
of NC (Charlotte/Raleigh- Durham). The WSSI-P shows low-to-
moderate chances (20-50%) for Extreme Impacts (per the WSSI=20
legend: extremely dangerous conditions, life saving actions may be
needed) in southern NC, including the I-95 corridor from=20
Fayetteville, NC to Florence, SC. Along the coast, WSSI shows Major
to locally Extreme conditions along VA Beach on south into the=20
northern OBX and along the north and east-facing shores facing the
Pamlico and Albemarle sounds, largely due the blizzard potential=20
and heavy snow. This speaks to the severity of this major winter=20
storm in the Carolinas. Lastly, with frigid temperatures in the=20
storm's wake on Sunday and lasting into Tuesday, the snow will not=20
melt much following the conclusion of the storm. Any melting that=20
occurs thanks to daytime heating is likely to cause refreezing on=20
untreated roads and surfaces. Residents in the Carolinas should=20
finish preparations as soon as possible, as road conditions will be
treacherous Saturday and into the first half of next week.

Elsewhere, travel disruptions are possible as far south and west as
the Atlanta metro area where the WSSI (as of this discussion's
issuance) shows Minor Impacts. Look for measurable snow to cause
hazardous travel as far west as the TN Valley and as far south as
Savannah where snowfall accumulations up to 1" is possible.
Moderate Impacts (hazardous travel and some infrastructure
impacts) are also forecast in Charleston, SC in the Smokeys/Blue=20
Ridge of western NC/TN, and as far north as the southern Richmond,=20
VA suburbs. Impacts are still unclear in southeast MA, but expect=20
blowing snow to cause reduced visibilities in the southeast MA=20
islands.=20


...Great Lakes...
Days 1-2...

Cyclonic flow will continue to favor lake effect snow across the=20
Great Lakes into the first half of the weekend. Frigid 850mb=20
temperatures will persist with temperatures around -18 to -24C,=20
which are below the 10th climatological percentile. WNW flow will=20
turn more northerly (even NNE for a time) as the sharp 500mb=20
shortwave passes over the Great Lakes tonight. On Friday, northerly
flow continues Friday with NNE flow possible into Chicagoland=20
carrying a LES band into the region overnight into Saturday.=20

Latest guidance has favored the heavier snow over far northwest=20
IN, although localized totals approaching 4" along the Lake Michigan
shores in Chicago are possible. Most snowfall winds downs late=20
Saturday into early Sunday as surface high pressure builds in overhead.
Single band off Lake Ontario will weaken starting this afternoon=20
but persist through Friday. For days 1-2, WPC probabilities for at=20
least 4 inches of snow are >50% over parts of the Michigan U.P. and
downwind of Lake Ontario near Oswego, where additional snowfall up
to 8" are possible.

...Northern Great Plains & Upper Midwest...
Days 1-3...

Two rounds of snow are expected; one this evening and into Friday
morning, then the other starting late Friday night and continuing
into the weekend. Weak 850-700mb WAA and FGEN will support light
snow over the western Dakotas and into the Nebraska Sand Hills
tonight and Friday AM. Snowfall totals are likely to range between
1-3" in these areas by the time snow concludes late Friday=20
morning, with the Black Hills sporting low chances (10-30%) for=20
snowfall total over 4". By Friday night, a Pacific shortwave trough
escorts Pacific moisture eastward into the Northern Plains=20
Saturday morning, then into the Upper Midwest Saturday evening into
Sunday. Patches of freezing rain in the northern High Plains on=20
late Friday into Saturday are expected given the favorable=20
overrunning from WAA at low-mid levels and sub-freezing surface=20
temps. Farther east, snow is the more likely precip type from the=20
Red River of the North on south to the Missouri Valley, then east=20
to the Mississippi river and MN Arrowhead. Snow totals are forecast
to range between 1-3" in these areas late Saturday into Sunday.=20
Some hazardous travel is possible, especially where roads=20
temperatures are likely below freezing in the wake of the recent=20
extreme cold.


Mullinax



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!9uwfHTIrXu4nB5pX8IiYt7LWwCT8oOZLhh6Q6IBpUX5Qs= 3ag7Wrua_Ul_oXoc_41EI5uC8IA5fYogem_z21P6LZ1O9o$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!9uwfHTIrXu4nB5pX8IiYt7LWwCT8oOZLhh6Q6IBpUX5Qs= 3ag7Wrua_Ul_oXoc_41EI5uC8IA5fYogem_z21PLNrxWmE$=20



$$

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FOUS11 KWBC 300739
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
239 AM EST Fri Jan 30 2026

Valid 12Z Fri Jan 30 2026 - 12Z Mon Feb 02 2026


...Southern Appalachians, Mid-Atlantic, & Southern New England...=20
Days 1-3...

...A major winter storm is expected to produce heavy snowfall and=20
blizzard conditions across the southern Mid-Atlantic...

Meteorological Overview...

An arctic air mass anchored over the eastern U.S. will set the=20
stage for an amplifying shortwave trough over the OH Valley to=20
produce a major winter storm over the southern Appalachians and=20
southern Mid-Atlantic beginning later this afternoon and continuing
into the weekend. Snow over the TN Valley this morning will move=20
into the southern/central Appalachians this afternoon due to low-
level WAA, increasing PVA aloft, and upslope enhancement. As the=20
upper trough sharpens over/near the OH/MS Confluence, a robust=20

100kt 500mb jet streak will place its divergent left-exit region=20

over the southern Mid-Atlantic and snow will envelop much of the=20 Appalachians and Piedmont of the Southeast early Saturday morning.=20

On Saturday, the 500mb shortwave will take on a N-S neutral tilt=20
over the TN Valley and close off as it enters NW GA. PVA becomes=20
maximized over the Southeast while a surface low spawns along a=20
coastal front east of the Carolinas (with an additional surface low
moving out of the Bahamas). As the 850mb low deepens over northern
GA and heads east into SC, easterly 850mb theta-e advection will=20
direct low-level moisture around the 850mb low and support a band=20
of moderate-to-heavy snow from northeastern GA to central SC.=20
Farther north, the same tongue of 850mb theta-e is funneling along=20
the 850mb front to the north of the 850mb low track from northern=20
SC on east through much of NC. This is where the deformation zone=20
is likely to form, pivoting over central to eastern NC and northern
SC with 1-2"/hr snowfall rates likely. This band of heavy snow is=20
likely to reach farther east toward the Outer Banks (HREF=20
probabilities of >1"/hr at 00Z Sun, the end of the run, are >30%)=20
where 700mb FGEN is more ideally placed to support strong vertical=20 velocities within a fully saturated DGZ. These bands of heavy snow=20
in eastern NC and southeast VA depict 700-500mb lapse rates=20

6.5C/km Saturday afternoon and evening. It is here where not only=20

2"/hr snowfall rates are achievable, but so is the likelihood for=20 thundersnow. Note that the intense vertical velocities in eastern=20
NC and extreme southeast VA may result in some subsidence in north-
central NC and south-central VA. Snowfall is still likely to reach
warning criteria, but these regions are potentially susceptible to
lesser snowfall amounts as they are caught between the influence=20
of the strong upper-low to the south, and the strengthening coastal
low.

Speaking of the coastal low, along the VA/NC/SC coasts, not only=20
will the deformation zone of heavy snow pivot through, but the=20
explosive deepening of the storm east of Cape Hatteras will support
strong to potentially damaging wind gusts. ECMWF shows low=20
pressure south of Hatteras around 1008mb 12Z Saturday dropping to=20
around 970mb by 12Z Sunday east of Hatteras, indicative of rapid=20 intensification. With strong high pressure to the west, a strong=20
isallobaric flow will develop in response, creating wind gusts=20
along the DelMarVa coast on south through the Outer Banks that=20
could approach hurricane-force at times. These coastal areas=20
overlap with the ECMWF EFI in >0.8 values for both snow and wind,=20
making these areas most susceptible to blizzard conditions. Not to=20
be ignored either, strong wind gusts atop the Smokeys and Blue=20
Ridge are likely to top 60 mph as well, resulting in possible=20
blizzard conditions in those higher elevations of the southern=20
Appalachians. Power outages are likely in some parts of the=20
southern Mid-Atlantic, particularly areas at risk for those=20
hurricane-force wind gusts along the VA/NC coast.

Latest trends nudged the QPF footprint a bit southward but still=20
focused on NC into SC and grazing southeastern VA. By Sunday, the=20
trend of the system as it makes its closest pass to New England is=20
to be a bit farther southeast (away from the coast), and have=20
trended down the snow there in response. Locations that remain=20
susceptible are Cape Cod, Martha's Vineyard, and especially=20
Nantucket where WPC probabilities for at least 4 inches of snow are
around 50%.


Snowfall & Impacts...

For the event, WPC probabilities for at least 8 inches of snow are

50% from the Blue Ridge/Smokeys eastward across most of NC and=20

half of SC and along the VA/NC border. Eastern NC has the highest=20
chances (30-50%) of at least a foot of snow, depending on and band=20 placement. For context, some locations may see snowfall amounts not
seen since the 1970s/1980s (e.g., Feb. 1973, March 1980, or Dec.=20
1989) and could be a top ten event snowfall.=20

The snowfall could also be highly disruptive, not just during the=20
event, but for days after it is long gone. WSSI shows an expansive=20
area of Major Impacts (considerable disruptions to daily life;=20
dangerous to impossible travel, widespread closures, disruptions to infrastructure) from central SC (including Columbia, SC) through=20
the eastern two-thirds of NC (Charlotte/Raleigh-Durham). Along the=20
coast, WSSI shows Major to locally Extreme conditions from the=20
VA/NC border southward into the OBX and along the north and east-=20
facing shores of the Pamlico and Albemarle sounds, largely due the=20
blizzard potential and heavy snow. This speaks to the severity of=20
this major winter storm in the Carolinas. Lastly, with frigid=20
temperatures in the storm's wake on Sunday and lasting into=20
Tuesday, the snow will not melt much following the conclusion of=20
the storm. Any melting that occurs thanks to daytime heating is=20
likely to cause refreezing on untreated roads and surfaces.=20
Residents in the Carolinas should finish preparations as soon as=20
possible, as road conditions will be treacherous Saturday and into=20
the first half of next week.

Elsewhere, travel disruptions are possible as far south and west=20
as the Atlanta metro area where the WSSI shows Minor impacts with a
chance for an inch or so of snow on Saturday. Measurable snow may=20
cause hazardous travel as far west as the TN Valley and as far=20
south as Savannah where snowfall accumulations up to 1" are=20
possible. Moderate impacts (hazardous travel and some=20
infrastructure impacts) are also forecast in Charleston (SC), the=20 Smokeys/Blue Ridge of western NC/TN, and as far north as the=20
southern Richmond, VA suburbs. Impacts are still unclear in=20
southeast MA, but any snowfall will likely be accompanied by gusty=20
winds, causing blowing snow and reduced visibilities.=20


...Great Lakes...
Day 1...

Cyclonic flow will continue to favor lake effect snow across the=20
Great Lakes for another 36 hours or so. Frigid 850mb temperatures=20
will persist (around -18 to -24C, which are below the 10th=20
climatological percentile) over the rapidly freezing lakes. The N-S
band over Lake Michigan this morning will likely graze the WI/IL=20
shore before aiming into NW Indiana this evening/overnight as the=20
elongated vorticity lobe swings through. WPC probabilities for at=20
least 4 inches of snow are highest (40-60%) around Gary, IN.=20
Leftover lake snow on northerly flow will relax on Saturday as high
pressure briefly builds in from the west.=20


...Northern Great Plains, Upper Midwest, and western Great Lakes...
Days 1-3...

Tonight, a Pacific shortwave trough escorts Pacific moisture=20
eastward into the Northern Plains by Saturday morning, then into=20
the Upper Midwest Saturday evening into Sunday. Patches of freezing
rain in the northern High Plains on late Friday into Saturday are=20
expected given the favorable overrunning from WAA at low-mid levels
and sub-freezing surface temps. Farther east, snow is the more=20
likely precip type from the Red River of the North southward to the
Missouri Valley, then east to the Mississippi River and MN=20
Arrowhead/U.P/WI. Snow totals are forecast to range between 1-3" in
these areas late Saturday through Sunday into early Monday. Some=20
hazardous travel is possible, especially where roads temperatures=20
are likely below freezing in the wake of the recent extreme cold.


Fracasso/Mullinax


...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!_3gsfWHd4Rifi_CbV855Uh95BwMUxebkCOtdGLmsOVMQr= 5vQiqjacEqqVbSCNFdjb1Vfzm2V8IUKW9U7ZZxrzndtSh8$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!_3gsfWHd4Rifi_CbV855Uh95BwMUxebkCOtdGLmsOVMQr= 5vQiqjacEqqVbSCNFdjb1Vfzm2V8IUKW9U7ZZxr0nsBM1M$=20



$$

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FOUS11 KWBC 301835
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
135 PM EST Fri Jan 30 2026

Valid 00Z Sat Jan 31 2026 - 00Z Tue Feb 03 2026


...Southern Appalachians, Mid-Atlantic, & Southern New England...=20
Days 1-2...

...A major winter storm is expected to produce heavy snowfall and=20
blizzard conditions across the southern Mid-Atlantic...

The synoptic evolution continues to support a major winter storm,
primarily focused over the Carolinas, but questions about the
details continue.

The event begins this evening, as snow breaks out across the
southern Appalachians of NC/TN. This initial development of snow
will be in response to increasing synoptic ascent within strong
mid-level divergence downstream of a pivoting shortwave digging out
of the Great Lakes. As this shortwave dives southward out of the
Great Lakes, it will rapidly deepen into an impressive closed low
by 12Z Saturday over the Tennessee Valley, and then continue to
dive southeast, reaching the GA/SC coast by 00Z Sunday. This will
produce extreme anomalies of more than -5 sigma with respect to
500mb heights according to NAEFS across the Southeast/Gulf Coast,
indicative of how rare and extreme this setup will be. As the upper
low deepens and drops southward, forcing will intensify in response
to not only the mid-level divergence noted above, but additional
robust height falls, and increasing jet-level diffluence as a
downstream subtropical jet streaks strengthens across the Gulf and
then begins to arc poleward along the Southeast coast. This will
help generate surface cyclogenesis along the coast of the
Carolinas, with dual low-pressure systems progged, each one
deepening along the intense baroclinic gradient positioned offshore
owing to the recent extremely cold air blanketed across the eastern
CONUS.

The secondary surface low, which is likely to be the more intense
feature as it explosively intensifies Saturday night into Sunday
(maybe reaching into the 960s offshore) is progged to pivot more
east than northeast along the coast, so the heavy precipitation
should be generally confined to the Carolinas, southern VA, and
maybe Cape Cod as it pulls away. While there is continued
uncertainty into the exact amounts of precipitation due to dry air
aloft and intense mesoscale ascent that will drive bands of heavy
snow, there is high confidence in this overall synoptic evolution,
resulting in high confidence in the most impacted areas.

The column will be extremely cold, so other than possibly some
light rain along the coast to start the event, this will be an
all-snow scenario with above-climo SLRs, a rarity for this part of
the country. As noted above, the snow begins across the
Appalachians Friday evening and then expand rapidly to the south
and east as the upper low dives towards the Gulf and low pressure
development occurs offshore. This expansion of precipitation will
be driven primarily by increasing 850mb easterly flow, tapping into
the growing theta-e ridge offshore, with the resultant WAA leading
to the expanding snow shield, Some of this WAA could be intense as
reflected by strengthening 925-700mb fgen, well aligned into the
deep DGZ (>70% chance of at least 100mb of DGZ depth according to
the SREF). This will support not only expanding snowfall, but
intensifying snowfall such that by 00Z/Sunday at least moderate
snowfall rates should encompass nearly the entirety of the
Carolinas and into northeast GA and southern VA.=20

After 00Z Sunday is when the heaviest snow and most notable impacts
are expected as the low offshore deepens rapidly. This will pivot
winds to more N/NE across the region, and as a deformation axis
pivots west of the surface low and the cold conveyor sets up across
the Atlantic and into the eastern Carolinas, more intense ascent=20
and greater moisture should result in extreme (for this region)=20
snow rates. Cross-sections indicate a broad region of favorable=20
conditions for CSI, or even CI (thundersnow), and the HREF snow-=20
rate probabilities peak above 50% for 1"/hr suggesting at least a=20
potential for 2"/hr within a pivoting band somewhere in eastern NC=20
or SC, and this is additionally supported by the WPC prototype
snowband tool. These heavy snow rates will be accompanied by=20
strong winds that may gust 35-50 mph, higher at the coast and in=20
the mountains, suggesting near blizzard conditions in many areas.=20
While uncertainty remains into how dry air in the mid- level may=20
impact snow amounts on the broad scale, locally very significant=20
snowfall accumulations are likely, especially within these bands,=20
during D2. By Sunday afternoon the low will pull away bringing an=20
end to the snowfall and leaving just cold windy conditions in its=20
wake.

The exception will be across far southeast Massachusetts and onto=20
Cape Cod and the Islands where, despite a subtle southeast trend in
today's model guidance, periods of moderate snow are still expected
due to onshore flow and sufficient synoptic ascent into the
moistening column. A period of moderate snowfall is likely, with
some local enhancement south of Boston and on the Outer Cape due to
ocean influences, Sunday aftn/eve.

WPC probabilities for the event are quite robust for both the
Appalachians and eastern North Carolina, where they are above 50%
for 8+ inches, and 30-50% for 12+ inches. The greatest potential=20
for more than 12 inches appears to be eastern NC where the=20
deformation band may pivot, but a widespread 4-8" snowfall appears=20
likely from southern VA through northern SC, with impactful=20
accumulations expected in areas like Richmond, VA, Charlotte and=20
Raleigh, NC, Columbia, SC, and even into Atlanta, GA. Farther=20
northeast, WPC probabilities are 30-50% for 4+ inches across the=20
Cape and Islands.

Key Messages are in effect for this storm, and are linked below
(Key Message #2).=20


...Great Lakes...
Day 1...

Potent shortwave diving southward within broad cyclonic flow into=20
the Tennessee Valley Saturday morning will rapidly sharpen the
eastern CONUS trough leaving pronounced CAA on northerly flow in
its wake. This will result in continued lake effect snow (LES),
especially in the favored north snow belts south of Lake Ontario
and especially south of Lake Michigan where the long fetch of the
lake will be maximized to produce a narrow band of heavy snowfall.
Although the lakes are cooling and have much higher ice coverage
than a week or two ago, frigid 850mb temperatures moving overhead
will create strong delta-Ts to support snowfall rates that have a
30-40% chance (from the HREF) of exceeding 1"/hr, greatest across
NW Indiana. While some light accumulations are likely south of Lake
Ontario, WPC probabilities for 4+ inches are confined to NW IN
where they reach 30-50%.


...Northern Plains through the Upper Midwest and Great Lakes...=20
Days 1-3...

A shortwave emerging from the Pacific will crest the ridge over the
Pacific Northwest and then dive slowly southeast into the Northern
Plains and then amplify into a deeper trough as it moves into the
Great Lakes and then elongate towards the Tennessee Valley. This
feature will generally be of modest amplitude and remain
progressive, so large scale forcing for ascent will be modest and
driven by mid-level divergence downstream of the trough overlapping
modest warm advection/isentropic ascent. The result of this will be
axes of both light freezing rain and snow in many areas from
eastern MT through the western Great Lakes. WPC probabilities for
2"+ of snowfall are as high as 30-50% D2 across central/northern
MN, and similar for parts of the U.P. and western L.P. of MI D3.
For freezing rain, WPC probabilities are as high as 30% for 0.1"=20
in western ND on D1, but are generally less than 10% elsewhere=20
through the period. However, light freezing rain accreting above=20
0.01" is possible for much of Montana and the Dakotas.

Weiss



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!_zv2HEUaCxHmrxcjxPpQ_d45hb_EFdwDQXzo01Egj7qkP= UXe0KoqO0O81tc8GJAqH6nRw9ZPdRN7lhhSqjXZph7rlAQ$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!_zv2HEUaCxHmrxcjxPpQ_d45hb_EFdwDQXzo01Egj7qkP= UXe0KoqO0O81tc8GJAqH6nRw9ZPdRN7lhhSqjXZerjYTzs$=20



$$

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FOUS11 KWBC 310710
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
210 AM EST Sat Jan 31 2026

Valid 12Z Sat Jan 31 2026 - 12Z Tue Feb 03 2026


...Southern Appalachians, Mid-Atlantic, & Southern New England...=20
Days 1-2...

...A major winter storm is expected to produce heavy snowfall and=20
blizzard conditions across the southern Mid-Atlantic...

Sharp mid-level trough over the mid-MS Valley early this morning=20
will close off into a potent upper low over Middle TN by 12Z. The=20
pattern over the East Coast will feature an increasingly amplified=20
pattern (e.g., strengthening S-shaped upper jet) that will support=20
explosive cyclogenesis off the Carolina coast this=20
evening/overnight. With an arctic air mass already in place, nearly
all of the precipitation will be snow even at onset. The system=20
will quickly lift up the coast (outside the 40/70 benchmark) and=20
clip southeastern New England as it races into Atlantic Canada=20
tomorrow.=20

First part of the system is underway over the southern=20
Appalachians with light to modest snow over the Smokeys into SW VA=20
beneath lower-level FGEN and incoming height falls/PVA. Snow will=20
expand southward today over WNC and Upstate SC as well as northeast
GA as the upper low tracks over ATL to CHS by this evening. To its
north, near the path of the developing 850mb low, the snow could=20
fall heavy at times today with 1"/hr rates possible (10-40% chance=20
per the CAM guidance) into the Charlotte metro. As the upper low=20
reaches the coast around 06Z Sun, banded snow could sink=20
southeastward into northeastern SC (Myrtle Beach/The Grand Strand).
By this time, the coastal low will have begun its rapid=20
intensification, which leads into the other part of the system.=20

With the coastal low intensifying through the 990s to 970s mb, N=20
to NE flow at the surface over eastern and northeastern NC into=20
extreme southeastern VA will increase as snow continues to fall.=20
The increasing 850mb northeasterly/easterly flow, tapping into the=20
growing theta-e ridge offshore, coupled with WAA and strengthening=20
925-700mb FGEN, will support >1"/hr rates over eastern NC after 00Z
Sun. Deformation axis should pivot west of the surface low and the
cold conveyor sets up across the Atlantic and into the eastern=20
Carolinas to support those rates. Cross-sections indicate a broad=20
region of favorable conditions for CSI, or even CI (thundersnow),=20
which is not unusual in highly dynamic and rapidly intensifying=20
systems. The column is quite cold, and SLRs should be well above=20
climo with a deep DGZ (>13:1 to near 20:1). These heavy snow rates=20
will be accompanied by strong winds that may gust 35-50 mph, higher
at the coast, suggesting near-blizzard conditions in many areas.

One question in the forecast, per the 00Z guidance, is what=20
happens in between these two main drivers of heavier snow areas;=20
i.e., in the I-85/95 corridors in NC. Some CAM guidance shows an=20
extreme min (near zero snow) while other guidance shows at least=20
several inches. CAM guidance could be overdoing the mesoscale=20
response of oscillatory subsidence/lift surrounding the system, but
it certainly is unusual to see this much spread just before the=20
start of the event. Trimmed down the amounts here from the previous
forecast but not to the extent of the 00Z CAMs.=20

By Sunday afternoon the low will pull away bringing an end to the=20
snowfall and leaving just cold windy conditions in its wake. To the
northeast, despite a track just outside the 40/70 benchmark, the=20
expansive system will likely clip far southeast Massachusetts=20
(southeast of I-95) and Cape Cod and the Islands where periods of=20
moderate snow are expected due to onshore flow and sufficient=20
synoptic ascent into the moistening column. A period of moderate=20
snowfall is likely, with some local enhancement south of Boston and
on the Outer Cape due to ocean influences, Sunday aftn/eve.

WPC probabilities for at least 6 inches of snow are >50% over much
of western NC, across the border to upstate SC, southeastward to=20
the coast, and the northeastward up the coast into extreme=20
southeastern VA. Lower probabilities around 30% exist along the VA=20
border and over southwestern SC. Mesoscale bands will likely=20
enhance snowfall over some areas resulting in >10-12" snow. A=20
broader area of light snow is expected surrounding the system, with
WPC probabilities for at least 1" of snow >50% as far west as=20
Atlanta, south to near Savannah, and on the north side up to=20
Richmond, VA and Salisbury, MD on the DelMarVa. In MA, WPC=20
probabilities for at least 4 inches of snow are >30% over the Cape=20
and Martha's Vineyard but >50% over Nantucket.=20


Key Messages are in effect for this storm, and are linked below=20
(Key Message #2).=20


...Northern Plains through the Upper Midwest and Great Lakes...=20
Days 1-3...

And advancing warm front over the western High Plains this morning
will continue eastward, bringing the chance for some snow and=20
freezing rain as milder Pacific air overruns the cold surface. The=20
system will continue eastward Sunday into the western Great Lakes=20
and through MI to the eastern Great Lakes Monday. Amounts will be=20
light, generally 1-3", as the system remains progressive. WPC=20
probabilities for at least 4" are around 10% over portions of the=20
Red River Valley (ND/MN border) and perhaps the Keweenaw Peninsula=20
wit some lake enhancement after the front moves to the east.=20


Fracasso/Weiss


...Winter Storm Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!4XEwcjZbPCsaopLdDZHr3UrVyP5HfOPX16r-Ffei8ZPsV= DY7_6OXc-aU-DKV2da-bl6n6tCr8zwqm953Cu8HX5EO-2M$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!4XEwcjZbPCsaopLdDZHr3UrVyP5HfOPX16r-Ffei8ZPsV= DY7_6OXc-aU-DKV2da-bl6n6tCr8zwqm953Cu8H32009l4$=20



$$

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FOUS11 KWBC 311936
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
236 PM EST Sat Jan 31 2026

Valid 00Z Sun Feb 01 2026 - 00Z Wed Feb 04 2026


...Southern Appalachians, Mid-Atlantic, & Southern New England...=20
Day 1...

...A major winter storm will produce heavy snowfall across the
southern Mid-Atlantiuc and blizzard conditions along the North
Carolina coast through tonight and into Sunday morning...

The major winter storm is unfolding with periods of snow, falling=20
heavily at times, from the southern Appalachians and eastern GA on=20
east through the Carolinas and into far southern VA. This morning,=20
the 850mb low has formed and is tracking towards southern SC with a
tongue of rich 850mb theta-e air rotating around the northern and=20
western flanks of the low. As the low strengthens, so does the=20
easterly fetch supplying Atlantic moisture, resulting in a=20
broadening shield of snow from as far west as the Atlanta metro to=20
even as far south as Savannah, GA today. As strong 500mb PVA moves
in aloft, a band of heavy snow is likely to unfold over eastern GA
that could then pivot over southern SC, including the Charleston=20
metro area. The heaviest snow rates are likely to occur north of=20
the 850mb low track where easterly low-level winds are enhanced via
upslope flow from the hills near Charlotte on west into the=20
southern Appalachians. Snowfall rates of 1-2" per hour are likely=20
there, resulting in dangerous to even impossible travel conditions.
WPC probabilities show moderate chances (40-60%) for additional=20
snowfall totals >4" from Charlotte on south into central SC and=20
eastward to northeast SC and the Cape Fear Tidewater region.=20

Central NC and southern VA are caught between the impressive=20
dynamics closer to the highly anomalous upper-low to the south and
west, and the developing coastal low that will rapidly strengthen=20
east ot the Outer Banks today and into tonight. Guidance has come into
better agreement on a depression in the expected QPF footprint=20
around the Raleigh-Durham area on north and east along I-85 into=20 south-central VA. While totals have trended down, it is=20
exceptionally cold with highs unlikely to get above the mid 20s=20
today. Plus, occasionally gusty winds this afternoon and evening=20
will cause reduced visibilities and blowing snow on roads. WPC=20
probabilities still show moderate-to-high chances (50-80%) for=20
snowfall totals >2" in these areas, with better odds for >4" on=20
southward along I- 95 and I-40. Snow will have no trouble sticking=20
and travel will be hazardous through this evening and into tonight.
Expect slick roads to persist into Sunday as temperatures will=20
struggle to get above freezing, and any melting that does occur on=20
Sunday on roadways has a high chance to refreeze Sunday night and=20
Monday morning.

Farther east into eastern NC and southeast VA, the storm system
along the coast will rapidly strengthen by as much as 40mb in 24
hours. Not only will a band of 1-2"/hr snowfall rates ensue this
afternoon and into tonight, but wind will ramp up in intensity
significantly, especially along the Outer Banks and on north/east
facings shores of the Pamlico and Albemarle Sounds. Steepening
lapse rates as the mid-upper level low approaches the warmer shelf
waters will also support some instability in the 850-500mb layer,=20
allowing for thundersnow to be a potential phenomenon for those in=20
eastern NC. Snow will continue over the eastern tidal areas of NC=20
and southeast VA through early Sunday morning, but snow should=20
taper off by midday Sunday as the powerful winter storm races east=20
into the west Atlantic. WPC probabilities show moderate- to-high=20
chances (50-80%) for snowfall totals >6" from the Myrtle Beach area
and the Cape Fear region on north through much of eastern NC.=20
Given the robust 1-2"/hr rates in eastern NC, there is a low-to-
moderate chances (30-50%) for localized snowfall totals to surpass=20
12" by the time this event concludes late Sunday morning. As=20
mentioned above, the bitter cold in wake of the storm will keep=20
travel on all roadways across eastern and southern NC treacherous=20
into the start of the work/school week.=20

Lastly, trends have been to gradually decrease snowfall totals in
southeast MA, although some measurable snow and blowing snow is
likely over Martha's Vineyard, Nantucket, and the MA Capes. WPC
probabilities show low-to-moderate chances (30-60%) for snowfall
totals >4" here, with Nantucket sporting the highest chances for

6" given their closer proximity to the winter storm on Sunday.

Key Messages are in effect for this storm, and are linked below=20
(Key Message #2).=20


...Northern Plains through the Upper Midwest and Great Lakes...=20
Days 1-3...

An advancing warm front associated with low pressure over southern
Canada is tracking across the North Central U.S. today will=20
continue eastward, producing light snow and minor freezing rain in=20
the Northern Plains as milder Pacific air overruns the cold=20
surface. The warm front marches eastward Sunday into the Upper
Midwest and Great Lakes, then into Michigan and the eastern Great=20
Lakes Monday. Amounts will be light, generally 1-3", as the system=20
remains progressive. Another round of light snow arrives in the
northern High Plains on Monday and ending Monday night, but totals
are likely to be below 3 inches.


...Ohio Valley & Central Appalachians...
Day 3...=20

The shortwave trough responsible for light snow in the northern
High Plains on Monday dives south into the Middle MS Valley early
Tuesday morning and races into the OH Valley by Tuesday afternoon.
Weak 850-700mb WAA and a tongue of 700-300mb moisture aloft will be
available aloft and will allow for snowfall. Most snowfall amounts will
be generally a coating-2", although the central Appalachians in=20
eastern WV have low-to-moderate chances (30-50%) for snowfall=20
amounts >2". This weak feature has a chance to produce light snow=20
in portions of the Mid-Atlantic on Wednesday.


Mullinax



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!_FsdXoLtiJKgZ9SEV8EVy4DoOUHafubqMkLCzThr-B36g= 9DWF1LlOJ9JGlBYJP21r3EHc_EHIKUVPBZmdQbPfoMGK1g$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!_FsdXoLtiJKgZ9SEV8EVy4DoOUHafubqMkLCzThr-B36g= 9DWF1LlOJ9JGlBYJP21r3EHc_EHIKUVPBZmdQbPrJyhzgw$=20



$$

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FOUS11 KWBC 010630
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
130 AM EST Sun Feb 1 2026

Valid 12Z Sun Feb 01 2026 - 12Z Wed Feb 04 2026


...Southeastern Massachusetts...
Day 1...

The powerful winter storm exiting the Carolinas this morning will=20
graze southeastern New England today with generally light snow but=20
very gusty winds. WPC probabilities for at least 4 inches of snow=20
are 10-30% over Nantucket and into parts of Cape Cod (e.g.,=20
Chatham).=20


...Northern Plains through the Upper Midwest and Great Lakes...=20
Days 1-3...

A surface front will move out of the Upper Midwest into the=20
western Great Lakes today then into Michigan and the eastern Great=20
Lakes Monday. Snow will be light, generally 1-3", as the system=20
remains progressive. Another round of light snow arrives in the=20
northern High Plains on Monday and ending Monday night, but totals=20
are likely to be below 3 inches. Some areas in the U.P. may see=20
several inches of the three-day period with modest lake effect snow
behind the front.=20


...Ohio Valley & Central Appalachians...
Day 3...=20

The shortwave trough responsible for light snow in the northern=20
High Plains on Monday will dive into the Middle MS Valley early=20
Tuesday morning and race into the OH Valley by Tuesday afternoon=20
and the Mid-Atlantic by Wednesday morning. Weak 850-700mb WAA and=20
mid-level moisture will favor light snowfall in a west-to-east=20
areas. Most snowfall amounts will be generally a coating-2", but=20
some upslope enhancement into the central Appalachians may allow=20
for a bit more. Here, WPC probabilities for at least 4 inches of=20
snow are low (10-20%). Light snow will extend eastward into the=20
Mid-Atlantic early Wednesday.


Fracasso


...Extreme Cold Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!9GBpM9epRWaJGrcPUfEKW7ns0MQShIt24-3aSTYra4iBS= yEc4zdUJy3kS0uC9meUdSdqsB6te8uKUm4NjS4o-T7c-Og$=20


$$

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FOUS11 KWBC 020713
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
213 AM EST Mon Feb 2 2026

Valid 12Z Mon Feb 02 2026 - 12Z Thu Feb 05 2026


...Pacific Northwest...
Day 1...

A weak shortwave and surface warm front will move through the
region this morning with some light snow for areas mainly above
4000ft, with snow levels rising sharply later today. WPC
probabilities for at least 4 inches of snow are >50% above 4000ft
or so.

...Great Lakes...
Day 1-1.5...

Weak system will spread slight snow across the Great Lakes (1-2")
today into Tuesday with some lake effect snow behind it, mostly
over the U.P. of Michigan. There, WPC probabilities for at least 4
inches of snow are 20-40%.

...Northern Plains...
Day 1...

A shortwave in southern Canada will dive southeastward through
North Dakota this morning, with generally light to locally modest
snow along a thermal gradient. Some banded snow could develop and
support a few inches of snow, and WPC probabilities for at least 4
inches are 30-70% over north central North Dakota.

...Ohio Valley, Central Appalachians, and Mid-Atlantic...
Days 2-3...

The shortwave over the northern Plains Day 1 (above) will dive
into the Mid-MS Valley tomorrow morning and through the Ohio Valley
tomorrow evening. At the same time, Gulf moisture will lit
northeastward through the Lower MS Valley to yield some light snow
on the northern side of the precip shield. WAA-driven snow is
likely along the Ohio River Tuesday morning eastward to the central Appalachians tomorrow evening and into early Wednesday, also
spreading to the Mid-Atlantic. Amounts will generally be light, but
some upslope enhancement in eastern WV could yield a few inches of
snow. WPC probabilities for at least 4 inches of snow are around
30-40% above 3000ft. 1-3" of snow is possible (>50% chance) from
around Cincinnati eastward. Lower chances of just 1" are seen along
the I-95 corridor from DC to PHL, but this could coincide with the
Tuesday evening rush hour or possibly Wednesday morning depending
on the speed of the system.

Some light freezing rain or drizzle is also possible with this
wave over KY/TN into VA/NC. Any ice is hazardous, but this could be
more problematic than usual due to the recent winter storm(s).


Fracasso


$$

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FOUS11 KWBC 021935
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
235 PM EST Mon Feb 2 2026

Valid 00Z Tue Feb 03 2026 - 00Z Fri Feb 06 2026


...Great Lakes...
Days 1-2...

A weak system will continue to spread light snow showers across
the Great Lakes tonight into Tuesday with some lake effect snow
following in its wake. Snowfall accumulations of 1-2" are likely
across portions of MI and western NY, with localized 20-40%
probabilities of >4" in the U.P of MI and localized 40-60%
probabilities downwind of Lake Ontario.


...Ohio Valley, Central Appalachians, and Mid-Atlantic...
Days 1-3...

A shortwave over the northern Plains will dive into the Mid-MS
Valley by Tuesday morning before reaching the Ohio Valley by
Tuesday evening. Ahead of this wave, weak surface low pressure will
develop over the Lower MS Valley, helping to draw Gulf moisture
northward. The increasing moisture and warm air advection combined
with large scale forcing for ascent within the left exit region of
a strengthening 250mb 100kt+ jet streak will yield a swath of
banded snow from southeast IN and southern OH Tuesday morning
eastward to the central Appalachians Tuesday evening into Wednesday
morning. WPC probabilities for snowfall >2" are 30-60% across a
fairly narrow corridor from southeast IN eastward along and just
north of the Ohio River and into WV. Banded snowfall could also
lead to localized higher amounts, with low but not zero
probabilities of >4" around 5-10%. Upslope enhancement may also
push accumulations above 4" in the higher elevations of WV, with
probabilities of 20-40% mainly above 3000ft.

Some light snow or flurries could survive the trip over the
central Appalachians into parts of the Mid-Atlantic late Tuesday
night into Wednesday morning, but trends for even just 1" of snow
have been decreasing with probabilities now only 10-20% across
portions of northern VA, northern MD, DE, and southern NJ. Still,
any snow combined with the recent cold and timing of early morning
rush hour could be enough to cause localized travel concerns. What
could be more interesting and worth monitoring is how much more the
wave develops as it begins to exit the Mid-Atlantic coast
Wednesday afternoon and evening. Latest trends have been a bit more
wintry across parts of southern VA and northern NC, and while poor
thermals are likely limiting probabilities of accumulating
snowfall at the moment, a deeper wave and greater dynamic cooling
could change that in the coming days.

In between the transition from snow to rain, some light freezing
rain or drizzle is also possible with this wave over KY/TN into
VA/NC. Any ice is hazardous, but this could be more problematic
than usual due to the recent winter storm(s).


Miller


$$

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FOUS11 KWBC 030804
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
304 AM EST Tue Feb 3 2026

Valid 12Z Tue Feb 03 2026 - 12Z Fri Feb 06 2026


...Great Lakes...
Day 1...

A weak system moving through the Great Lakes this morning will spread
light snow showers over the region with some lake effect snow
following in its wake. Snowfall accumulations of 1-3" are likely
across portions of the U.P. of Michigan and near Watertown, NY. WPC probabilities of >4" are low (10-20%).

Day 3...

A 140kt jet over south central Canada Thursday will help push a
warm front through the western Great Lakes, followed by a strong
arctic cold front that will cross into the region by Friday
morning. This will bring a period of snow focused on Michigan which
will lie near/north of the stronger height falls along the fronts.
Through 12Z Friday, generally light snow but increasing winds over
the region will usher in much colder air. WPC probabilities for at
least 4 inches of snow through 12Z Fri are low (10%) but blowing
snow could be the bigger hazard, especially near the lake shores.


...Ohio Valley, Central Appalachians, Mid-Atlantic, Carolinas...
Days 1-2...

A shortwave over the Corn Belt this morning will reach the Ohio
Valley this evening. Ahead of this wave, weak surface low pressure
will develop over the Lower MS Valley, helping to draw Gulf
moisture northward. The increasing moisture and warm air advection
combined with large-scale forcing for ascent within the left exit
region of a strengthening 250mb 100kt+ jet streak over the Mid-
South will yield a swath of banded snow from southeast IN and
southern OH eastward to the central Appalachians today into tonight.
Amounts will be light (Minor impacts per the WSSI) and WPC
probabilities for snowfall >2" are 30-60% across a fairly narrow
corridor from northern KY (CVG) eastward along and just north of
the Ohio River and into WV. Banded snowfall could also lead to
localized higher amounts, with low but non-zero probabilities of

4" around 5-10%. Upslope enhancement may also push accumulations

above 4" in the higher elevations of WV, with probabilities of
20-40% mainly above 3000ft.

Some light snow should crest the central Appalachians into parts
of the Mid-Atlantic late Tuesday night into Wednesday morning, but
this can sometimes dry up east of I-81. WPC probabilities for 1" of
snow are generally <15% along the I-66/Rt 50 corridor across
northern VA, DC, MD, and into DE. Still, any snow combined with
the recent cold could be enough to cause localized travel
concerns.

As the front continues southeastward, trailing shortwave energy may
slow the southern portion of the front over the Southeast, allowing
a weak area of low pressure to form over the southern Appalachians
on Wednesday. As the low moves slowly through GA/SC Wednesday
evening and off the coast early Thursday, moisture will linger over
southern VA and much of northern/western NC where temperatures are
marginally supportive of snow. During the overnight hours, dynamic
cooling could support some light accumulation of 1-2" over
southwestern VA and northern NC where WPC probabilities of >2" of
snow are 30-60%.

At the same time, enough northerly component of the wind could
drain some sub-freezing boundary layer air into eastern NC and
support light icing of around 0.01" or so. Any ice is hazardous,
but this could be more problematic than usual due to the recent
winter storm(s).


Fracasso/Miller



$$

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FOUS11 KWBC 031900
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
200 PM EST Tue Feb 3 2026

Valid 00Z Wed Feb 04 2026 - 00Z Sat Feb 07 2026


...Ohio Valley, Central Appalachians, Mid-Atlantic, Carolinas...=20
Days 1-2...

Increasing moisture and warm air advection ahead of a weak surface
low over the Mid South combined with large-scale forcing for=20
ascent within the left exit region of a strengthening 100kt+ upper=20
level jet streak will yield a swath of snow from eastern KY eastward
to the central Appalachians tonight into early Wednesday. Amounts=20
will be light (Minor impacts per the WSSI) and WPC probabilities=20
for snowfall >2" are 30-60% mainly across the higher elevations of=20
WV and southwest VA.

Some light snow should also crest the central Appalachians into=20
parts of the Mid-Atlantic late tonight into Wednesday morning, but
this can sometimes dry up east of I-81. WPC probabilities for 1"=20
of snow are generally <15% along the I-66/Rt 50 corridor across=20
northern VA, DC, MD, and into DE. Still, any snow combined with the
recent cold could be enough to cause localized travel concerns,
particularly during the Wednesday morning commute.

As the front continues southeastward, trailing shortwave energy may
slow the southern portion of the front over the Southeast, allowing
another weak area of low pressure to form over the southern=20
Appalachians on Wednesday. As the low moves slowly through GA/SC=20
Wednesday evening and off the coast early Thursday, moisture will=20
linger over southern VA and much of northern/western NC where=20
temperatures are marginally supportive of snow. During the=20
overnight hours, dynamic cooling could support some light=20
accumulations around an inch or so across southern VA and northern
NC, especially across the higher elevations of southwestern VA and
northwest NC where WPC probabilities of >2" of snow are 20-40%.

In the wake of the departing low pressure system, lingering low-=20
level upslope moisture combined with mid-level drying may lead to a
period of freezing drizzle across parts of eastern KY, southwest=20
VA, eastern TN, and western NC late tonight into Wednesday morning.
Anywhere the freezing drizzle is more persistent could produce a=20
light glaze of ice. Additionally, enough northerly component of the
wind could drain some sub-freezing boundary layer air into far=20
southeastern VA and eastern NC, supporting light icing of around=20
0.05" or so later Wednesday night into early Thursday morning.=20
While any ice is hazardous, the icing noted above could be more=20
problematic than usual due to the recent winter storm(s).


...Great Lakes, Central Appalachians, Mid-Atlantic...=20
Day 3...

A 140kt upper level jet over south central Canada Thursday will=20
help push a warm front through the western Great Lakes, followed by
a strong Arctic cold front that will dive to the south and east across
the region through the day on Friday. The left exit region of this
jet combined with a potent vort max will increasingly support=20
large scale forcing for ascent, with weak surface low development=20
possible downstream of the western Great Lakes. This will support=20
widespread snow showers and the potential for snow squalls from
MI and western NY to OH, PA, and WV starting late Thursday night=20
and continuing through the day on Friday. Some of the stronger=20
showers and squalls are looking increasingly likely to spill over=20
the central Appalachians into parts of the Mid-Atlantic later in
the afternoon, possibly impacting the evening commute. WPC=20
probabilities for >2" of snow are 40-70% across parts of MI,=20
northeast OH, northwest PA, and the higher elevations of southwest=20
PA and WV. Probabilities for >4" of snow are 10-20% for portions of
the U.P. of MI, northeast OH, and WV.=20

In the wake of the Arctic front, a blast of bitterly cold air will
encompass much of the Northeast heading into the weekend. For more
details, please reference the Extreme Cold Key Messages in the link
provided below.


Miller/Fracasso


...Extreme Cold Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!5j_1Fl9dotMFlsl07RquALPtLY120Rf8RXpm3UvO9h2Aq= WTyEVokCe1dREqejgH5zKFQcTSSV5HeegGtRiqqlHSH2qw$=20


$$

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FOUS11 KWBC 040716
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
216 AM EST Wed Feb 4 2026

Valid 12Z Wed Feb 04 2026 - 12Z Sat Feb 07 2026


...Southern Mid-Atlantic...
Day 1...

A cold front over the Southeast this morning and area of low=20
pressure over the southern Appalachians will make a slow march=20
eastward today with rain over much of the region but some light=20
snow on the northern side of the precipitation shield. Trailing=20
shortwave energy from the Lower MS Valley/Mid-South will slow the=20
front a bit tonight as temperatures cool just enough over southern=20
VA into northern NC for snow to fall and accumulate. In addition,=20
lingering moisture over eastern NC tonight combined with mid-level=20
drying may lead to some freezing rain and freezing drizzle. Though=20 accumulations will be light (0.01-0.05"), any freezing rain is=20
impactful to untreated surfaces. Precipitation will end from west=20
to east Thursday.

WPC probabilities of at least 2 inches of snow are 20-50% over=20
southwestern VA and barely 10% over northern/northeastern NC.=20


...Great Lakes, Central Appalachians, Northeast, Mid-Atlantic...=20
Days 1-3...

A warm front will push into the Upper Midwest and western Great=20
Lakes, aided by a 140kt upper level jet over south central Canada=20
on Thursday. Light and broad WAA-driven snow is forecast for=20
northeastern MN and across the Upper and Lower Peninsulas of=20
Michigan. This will be followed by a strong Arctic cold front that=20
will dive to the south and east across the region through the day=20
on Friday. The left exit region of this jet combined with a potent=20
vort max will support large-scale forcing for ascent across the=20
Great Lakes in the wake of the lead light snow. With the passage of
the Arctic front, snow squalls are possible from MI and western NY
to OH, PA, and WV starting late Thursday night and continuing=20
through the day on Friday. Some of the stronger showers and squalls
are looking increasingly likely to spill over the central=20
Appalachians into parts of the Mid-Atlantic later in the afternoon,
possibly impacting the evening commute on Friday. Upslope snow in=20
the central Appalachians should maximize Friday afternoon/evening=20
as the front moves through.=20

WPC probabilities for at least 4 inches of snow are low (10-40%)=20
across the U.P. of Michigan and west of Traverse City. Over western
NY and NW PA, surface low may move through the region and spur=20
more widespread snow along/behind the front and as winds turn more=20 northerly, picking up moisture off Lake Ontario. There, WPC=20
probabilities for at least 4 inches of snow are 20-50%. Finally,=20
over eastern WV, amounts will likely be the highest in the region=20
and WPC probabilities for at least 4 inches of snow are >70%,=20
especially above 2000ft.=20

In the wake of the Arctic front, a blast of bitterly cold air will
encompass much of the Northeast heading into the weekend. For more
details, please reference the Extreme Cold Key Messages in the=20
link provided below.

Fracasso


...Extreme Cold Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!7tsD76lSRVfHX36EwdU0bUH9sv7W5vUQCPqiaIzI-ixFR= Gd4LUnOvsu70q0yzEm9RwTuYw8BtsBuDJVbB7gEJeEI6qI$=20


$$

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FOUS11 KWBC 041942
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
242 PM EST Wed Feb 4 2026

Valid 00Z Thu Feb 05 2026 - 00Z Sun Feb 08 2026


...Southern Mid-Atlantic...
Day 1...

An area of low pressure riding along a cold front that is tracking
across the Southeast will bring some wintry precipitation on the
northern fringe of the precipitation shield along the VA/NC border
tonight. Rain and a wintry mix will change over to snow, while for
portions of central and eastern North Carolina, mid-level drying
with a slow exit of the low level moisture will support a period of
freezing drizzle, which could accumulate to a few hundredths of an
inch on untreated surfaces tonight. Both precipitation and
associated impacts should end within a couple hours of sunrise
Thursday.=20

WPC probabilities of 0.01 inches of ice is around 80% for portions
of North Carolina between Greenville and Fayetteville, and up to
30% for 0.10 inches of ice. Snow probabilities for an inch of snow
are between 20-40% along the VA/NC border, and up to 50% along I-81
southwest of Roanoke, VA.=20



...Great Lakes, Central Appalachians, Northeast, Mid-Atlantic...=20
Days 1-3...

A warm front will push into the Upper Midwest and western Great=20
Lakes, aided by a 140kt upper level jet over south central Canada=20
on Thursday. Light and broad WAA-driven snow is forecast for=20
northeastern MN and across the Upper and Lower Peninsulas of=20
Michigan. This will be followed by a strong Arctic cold front that=20
will dive to the south and east across the region through the day=20
on Friday. The left exit region of this jet combined with a potent=20
vort max will support large-scale forcing for ascent across the=20
Great Lakes in the wake of the lead light snow. With the passage of
the Arctic front, snow squalls are possible from MI and western NY
to OH, PA, and WV starting late Thursday night and continuing=20
through the day on Friday. Some of the stronger showers and squalls
are looking increasingly likely to spill over the central=20
Appalachians into parts of the Mid-Atlantic later in the afternoon,
possibly impacting the evening commute on Friday. Upslope snow in=20
the central Appalachians should maximize Friday afternoon/evening=20
as the front moves through.=20

WPC probabilities for at least 4 inches of snow are low (10-30%)=20
across the U.P. of Michigan and west of Traverse City. Over western
NY and NW PA, surface low may move through the region and spur=20
more widespread snow along/behind the front and as winds turn more=20 northerly, picking up moisture off Lake Ontario. There, WPC=20
probabilities for at least 4 inches of snow are 20-40%. While there
is a considerable amount of ice cover on the Great Lakes, just
under 50% according to the USNIC, there remains enough open water
on all but Lake Erie to expect there to be at least some
contribution of lake moisture to the column as the front moves
through. In addition to upslope into the U.P. of Michigan and
western New York, higher snow totals can be expected in these
areas.

Finally, over eastern WV, amounts will likely be the highest in=20
the region and WPC probabilities for at least 4 inches of snow are=20

70%, especially above 2000ft. Considerable upslope flow with

northwesterly winds orthogonal to the Appalachians should wring out
the most atmospheric moisture, resulting in the greatest snow
totals here, hence the highest probabilities.

In the wake of the Arctic front, a blast of bitterly cold air will
encompass much of the Northeast heading into the weekend. For more
details, please reference the Extreme Cold Key Messages in the=20
link provided below.

Fracasso/Wegman



...Extreme Cold Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!-L09wy298h8p0HixTwZRXJh9yemxGI5nIpYl1RfnPrfk3= P4EYhRUXRbBhtoQEcTsBOik16JFMlJIR31mdQRa5gP9iBg$=20



$$

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FOUS11 KWBC 050819
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
319 AM EST Thu Feb 5 2026

Valid 12Z Thu Feb 05 2026 - 12Z Sun Feb 08 2026


...The Carolinas...=20
Day 1...

A deep shortwave trough will track across the northern Gulf and
then off the Florida coast through this aftn. This will help
strengthen secondary low pressure off the coast of the Carolinas,
with some lingering moisture extending back onshore, at least
through the morning. However, forecast soundings indicate that
pronounced dry air above the surface will inhibit much in the way
of precipitation. However, what does fall, will occur in a sub-
freezing column, leading to a continuation of very light freezing
rain or freezing drizzle for a few hours after 12Z across the
eastern Carolinas. This is reflected by WPC probabilities that
indicate a 10-30% chance (locally 50% chance) of more than 0.01" of
ice, highest from Cape Fear through the Outer banks.


...Great Lakes, Central Appalachians, Northeast, Mid-Atlantic...=20
Days 1-3...

A fast moving shortwave diving out of Manitoba will race southeast
today, reaching the Mid-Atlantic states by Friday morning. This
lead impulse will be followed almost immediately by a second, more
strung out, shortwave, with this secondary impulse responsible for
driving a strong arctic cold front southward beneath it. This
secondary impulse will help develop a surface wave of low pressure
across Upstate NY Friday evening, with this low scooting rapidly
eastward to off the New England coast by the end of D2. The lead
cold front will trail off this low, with a secondary reinforcing
surge of arctic air occurring Saturday behind a secondary front.

Together, these features will result in an extended period of
moderate ascent, but in an environment with normal to below normal
PWs on the sharpening NW flow. Although the moisture will be
modest, the forcing will be sufficient to wring out snowfall across
the area, although most accumulation will be very light. There may
be a few exceptions:

1) Upslope snow into the Central Appalachians. This is expected
behind the first cold front beginning Friday aftn and then
intensifying Friday night before waning Saturday evening.
Intensifying N/NW flow will become quite strong and direct into the
terrain, with the cooling column providing a deepening DGZ into
which this ascent will maximize. Although atmospheric moisture is
modest, this flow will direct at least some Great Lakes enhanced
moisture to improve the potential for heavy upslope snowfall.
Initially, Froude numbers Friday and Friday night suggest critical=20
or blocked flow indicating the heaviest snowfall will be along or=20
just upwind of the Appalachians crests, but as flow becomes=20
unblocked on Saturday, more snow may spill over towards the east.=20
Still, the heaviest accumulations are likely in the higher terrain=20
and upwind areas, where WPC probabilities for the entire event=20
suggest a high risk (>70% chance) for at least 8" of snow, with=20
locally 12+" possible (30% chance).

The increasing W/NW flow behind the arctic front will also support
some enhanced lake effect snow (LES), especially in the favored=20
more N/NW snow belts south of Lake Ontario and Lake Superior. LES
is not expected to be extremely heavy or prolonged, but WPC
probabilities indicate a 70-90% chance for at least 4" south of=20
Lake Ontario, and a 30-50% chance across the eastern U.P. of=20
Michigan.

Finally, as a surface low strengthens well offshore and east of=20
the Mid-Atlantic states, increasing NW flow with a potential=20
inverted trough will focus some moisture and ascent across eastern=20
New England from near Portland, ME southward to Cape Cod, MA. The=20 combination of onshore flow and ocean effect snow combined with the
potential focused inverted trough may enhance snowfall along the=20
coast. The intensity of this snowfall is still quite uncertain as=20
most of it is early D3, but these inverted troughs can sometimes=20
pivot favorably for locally much heavier snowfall. Confidence is=20
modest at this time range due to wide variations in the models, but
current WPC probabilities indicate a 50-70% chance for at least 4"
of accumulation from Cape Ann southward through Cape Cod,=20
including the Boston metro area.

Finally, although not expected to be widespread, scattered snow
squalls are possible along the arctic front as it digs southward
Friday night into Saturday across the Northeast. Any convective
snow showers or squalls that develop will contain brief heavy snow
rates and strong winds, leading to hazardous travel.

Extremely cold temperatures this weekend have also prompted the
issuance of Key Messages related to this event. Those are linked
below.


Weiss


...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!9APqMvp9Avm9tP_63VeqcPXrzpjBn4ND1yCgQrSuQdPno= TECi6gsEfU5JgOPvZFmrGY8NS2tW8VKC-qRNjuSxNNPVTI$=20



$$

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FOUS11 KWBC 051918
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
218 PM EST Thu Feb 5 2026

Valid 00Z Fri Feb 06 2026 - 00Z Mon Feb 09 2026


...Great Lakes, Central Appalachians, Northeast, Mid-Atlantic...=20
Days 1-3...

A deep core low persists north of Hudson Bay through this weekend
with a focused shortwave trough plunging south from Manitoba
tonight, crossing the Great Lakes Friday, before deepening as it
pushes off the Mid-Atlantic Saturday. Rapid surface low development
is expected well east of New England on Saturday as surface high
pressure builds over the Upper Midwest, forming an intense pressure
gradient across the Northeast. A notable surge of Arctic air is
expected Friday night across the Northeast.

Extremely cold temperatures this weekend are discussed further in
Key Messages which are linked below.

The NW flow behind this shortwave will have ascent, but the
continental air and mostly ice covered Great Lakes will limit snow
rates across the Midwest. However, this NW flow will have
topographic enhancement over the central Appalachians Friday
afternoon/evening where rates will locally reach 1"/hr. The arctic
surge over this area is overnight Friday with powerful, potentially
damaging wind gusts as precip rates decrease. Day 1.5 snow probs
for >6" are 40-80% from the western edge of MD down the Allegheny
Highlands into western VA as well as the higher Apps along the
NC/TN border.

As the surface low strengthens and the whole system becomes
develops well off the Mid-Atlantic coast on Saturday, increasing=20
NW flow over an inverted trough will focus some moisture and=20
ascent across New England (outside of Maine).=20
Then on Saturday night there is potential for a focused snow band
to develop near of over Cape Cod which would have ocean
enhancements. As of now Day 2 snow probs for >4" are 40-60% for the
southern shore of Lake Ontario, along the spine of the Green Mtns,
and generally 30% over eastern Mass down through Long Island.
Values for >4" then peak around 40% over Cape Cod for Day 2.5.=20

Finally, although not expected to be widespread, scattered snow
squalls are possible along the arctic front as it digs southward
Friday night into Saturday from New York state down through central
WV. Any convective snow showers or squalls that develop will=20
contain brief heavy snow rates and strong winds, leading to=20
hazardous travel.


...Northwest...
Day 3...

Low pressure pushing northeast into the Gulf of Alaska Saturday
directs an elevated plume of moisture through the Pacific Northwest
Saturday afternoon through Sunday. Snow levels on the Cascades=20
rise to 6000 in WA and 7000ft in OR Saturday afternoon before
dropping to 5000ft in WA Sunday in moderate precip rates. Day 3
PWPF for >6" are 40-80% for the Cascade Volcanoes (above key
mountain passes) and the massif around North Cascades NP.


Jackson



...Cold Key Messages are in effect and linked below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!7KI4dATxiwGQnZk853B_9AzlywkL5ZjkFRAIwG6I2X03r= r6vHEFHnXsemfiTESuFux8NmHZX027MEkGNOGzSd9PYYDg$=20



$$

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FOUS11 KWBC 070706
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
206 AM EST Sat Feb 7 2026

Valid 12Z Sat Feb 07 2026 - 12Z Tue Feb 10 2026


...Northeast & Mid-Atlantic...=20
Day 1...

Extreme cold and dangerous wind chills overspread the Northeast=20
tonight and continue through Sunday with Key Messages in effect=20
and linked below.

The combination of an arctic cold front current racing through the
Ohio Valley/Interior Mid-Atlantic will combine with a strengthening
low pressure well offshore to produce extremely cold temperatures
and damaging winds for much of the region, with heavy snow for=20
parts of the area as well.

A shortwave driving the cold front southward will help generate
widespread light snow across New England and Long Island, but total
snowfall amounts are expected to be rather modest. Despite that,
briefly heavy snow rates combined with the rapidly increasing winds
will still result in impacts, especially to travel due to snow-
covered roads and low visibility. The greatest impacts, and likely
more substantial snowfall, is expected from far SW Maine, SE New
Hampshire, and along the eastern Coast of Massachusetts from Cape
Ann to Cape Cod where low-level convergence, onshore flow and
resulting ocean effect snow (OES) and an inverted trough will all
interact to enhance snowfall. There continues to be uncertainty as
to where the heaviest snowfall will occur. However, intense=20
snowfall rates of 1-2"/hr are possible (30-60% chance) thanks to=20
intense ascent into a lowering DGZ within the presence of some=20
instability. WPC probabilities are moderate (50-70%) for 4+ inches=20
from the Seacoast of NH through the Boston metro area, with locally
more than 8 inches possible (10-30% chance) and as reflected by=20
significant spread amongst the WSE plumes.


...Pacific Northwest and Northern Rockies...=20
Days 1-3...

Mid-level trough positioned off the Pacific coast will slowly track
eastward today and Sunday, with the primary trough axis finally
pushing onshore Sunday night as a shortwave lifts onshore near the
CA/OR coast. This shortwave will then continue to track east while deamplifying, reaching the northern High Plains by the end of the
forecast period.

This trough evolution will be accompanied by a modest subtropical
jet streak arcing meridionally downstream to provide overlapping
synoptic ascent. This lift will occur into a moistening column as
persistent SW flow ahead of the shortwave/trough axis will provide
a long duration of IVT exceeding 250 kg/m/s, with IVT max
potentially exceeding 500 kg/m/s (50-60% chance) which will lead to
two rounds of heavy precipitation extending from Oregon through=20
the Northern Rockies. Snow levels within the strongest IVT plume
will be 6000-7000 ft thanks to pronounced WAA, but will steadily
fall to 3000-4000 ft Monday as a cold front, driven by the
aforementioned trough, progresses southeast. This will allow for
heavier and more impactful snow across the Northern Rockies than
what is anticipated in the Cascades due to lower snow levels. 2-day
WPC probabilities indicate the heaviest snow is expected in the
vicinity of Glacier NP in the Northern Rockies where they exceed
70% for 12+ inches, and locally as much as 2 feet is possible in
the highest terrain. Elsewhere, WPC probabilities are high (>70%)
for 8+ inches across the Absarokas and Tetons near Yellowstone NP,
the Blue Mountains of OR, and across the highest peaks of the WA=20
and OR Cascades.



Weiss


...Extreme Cold Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!4Xa2oHMmm6KfYz7unG9Agh0MhfUQ7fqpY9sRHyH0zmenP= 8OIT453zr1s2_i_RtderGizZjFyR5DPVZVOSXZzX8SPp3g$=20



$$

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FOUS11 KWBC 181910
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
310 PM EDT Wed Mar 18 2026

Valid 00Z Thu Mar 19 2026 - 00Z Sun Mar 22 2026

...Upper Midwest to the Northeast...
Days 1-3...

A quiet pattern with respect to heavy snow and icing will continue,
with widespread heavy snow or significant icing not expected across
the contiguous U.S. through the end of the week.

Precipitation associated with a low-amplitude shortwave sliding
southeast across the Upper Midwest is expected to produce some
minor ice accumulations tonight from northern Wisconsin southeast
into southern Michigan and far northern Indiana.

Meanwhile, a more amplified shortwave to the north will spread
light snow from far northern Michigan to Upstate NY and northern
New England as it swings across southeastern Canada on Thursday.

A second shortwave will amplify over the northern Great Lakes on
Friday and move east across the Northeast on Saturday, bringing
additional light snow accumulations to the same regions. Apart
from some localized heavier amounts in the higher reaches of the
Adirondacks and the northern New England mountains, three-day snow accumulations are expected to top out at only an inch or two for
most of the impacted locations.

Pereira

$$

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