FOUS11 KWBC 250741
QPFHSD

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

Valid 12Z Sun Jan 25 2026 - 12Z Wed Jan 28 2026

...Ongoing major winter storm to bring crippling icing,
significant sleet, and heavy snow from the Southern Rockies/Plains
through the Southeast and up the Atlantic Coast into New England...

Meteorological Overview...
Forecast remains on track as a massive winter storm is underway
across a significant portion of the country, currently extending
from the southern Rockies to the Mid-Atlantic early this morning.
By the start of the forecast period (12z Sun), widespread moderate
to heavy snow, sleet, and freezing rain is expected to span from
New Mexico to New York and continue to primarily impact regions
from the Ohio/Tennessee valleys and Mid-Atlantic to New England
through the overnight hours tonight. This event is forecast to
gradually wane across New England and the Interior Northeast on Monday.

The driver of this winter storm is the interaction of a northern
stream trough diving out of the north-central U.S. this morning
along with a few southern stream impulses ejecting from the
southern Rockies and Plains. As these features accelerate eastward
today and interact into a more amplified and larger trough over
the central CONUS tonight, impressive subtropical moisture will
continue spreading east/northeast both from the Pacific and the
Gulf, with IVT exceeding the 97.5th climatological percentile
according to NAEFS. The rich moisture from the south will accompany
strong 850-700mb WAA that results in classic over- running along
an area of 850-700mb FGEN stretching from atop the Mid-MS and OH/TN
VLY to the Mid- Atlantic this morning, reaching New England this
evening and then finally exiting the Atlantic Coast on Monday. In
addition to the classic overrunning/WAA precipitation, the
placement of the upper jet as it strengthens and pivots poleward,
will support intense bands of snowfall (cross sections suggest a
high threat for CSI and even potential CI within the strongest WAA)
which will support snowfall rates of 1-2+"/hr at times where it is
all snow, and intense sleet/freezing rain rates in mixed zones.

Farther to the east, the intense CAD (Cold Air Damming) signature
east of the Appalachians will only slightly retreat through
tonight. With rapid warming aloft due to increasing southerly 850mb
winds over 50 kts and subfreezing temperatures remaining in the
low- levels, sleet is expected to be as far north as southern MD by
12z this morning and continuing marching northward through the day
as far as the southern New England coastline. This will cut down on
snowfall totals along I-95 from Washington D.C. to NYC, and will
also increase the potential for ptype to turn towards dangerous
freezing rain by late this afternoon.

With intense IVT pushing PWs to above the 99th percentile, there
will be plentiful moisture to work with everywhere from the OH VLY
through New England. This will support heavy precipitation
accumulations regardless of p-type, so substantial impacts are
expected for a large swath of the nation. The heaviest snow is
expected from the Ohio Valley into the Northeast (more outlined
below). Farther south, crippling icing is expected for parts of
AR/LA/MS/TN early today, as well as the Carolinas and Virginia
through tonight, with exceptional sleet accumulations of several
inches progged in between the snow and ice from Arkansas through
Kentucky, and then for portions of the Mid- Atlantic as well.

Heavy Snow/Sleet...
Snow will be winding down across the Southern Plains and Mid-MS VLY
by 12z this morning, but continues just east through the OH VLY. This
still supports an long swath of >6" of snowfall from IN to ME and
an increasing potential for >18" across the Interior Northeast and
New England.

48-hr WPC probabilities (most snow occurring within the first
24-hr period), are high (>70%) for an additional 8"+ from central
OH through central ME and most of New England. Probabilities for
18"+ have increased and are 50-80% across Upstate NY through much
of New England as far north as central VT/NH. A heavy band of
snowfall on the NW side of the low and within the strengthening jet
streak will support 1+"/hr snowfall across the Ohio Valley through
this afternoon as reflected by the WPC prototype snowband tool.
With this band likely translating along its long axis, heavy
snowfall will have a temporal extent sufficient for more than 8
inches. Locally 15+ inches is possible across southern OH.

The heaviest snow from this event is likely across New England and
the Interior Northeast where p-type changes are not likely. This
is also where the longest duration of heavy snowfall within both
WAA banded structures and then potentially a more
pivoting/laterally translating band will develop as secondary low
pressure skirts off the Mid- Atlantic coast and just inside the
Benchmark (40N/70W). This will support a longer duration of
2+"/hr snowfall, and WPC 48-hr probabilities reach above 90% for
12+ inches, and locally as much as 2 feet is possible (especially
in the Worcester Hills, Berkshires, and Catskills, as well north of
Boston along the coastal front) where WPC probabilities for 24"
are 20-40%. WPC's Snowband Probability Tracker (SPT) using the 00z
HREF is very impressive for 1-2"+/hr rates around 18Z near
northern NJ and eventually across New England beginning around 21Z
and lasting across eastern New England until 06Z tonight.
Regarding coverage of heavy snow, this will be a widespread 12"+
snowfall event for most of southern and central New England as well
as central/northern PA.

In addition, with the intense WAA, a warm nose aloft (generally
800-700mb) will gradually create a warm nose above 0C shifting
through the Mid-Atlantic. The cold depth below this warm nose
appears to be in many places above the 75th-90th percentile for
freezing rain, indicating primary sleet for these interior areas
as p-type transition occurs, with significant sleet accumulations
of multiple-inches expected. This will result in tremendous impacts
to travel in these areas.

The WSSI shows widespread Major Impacts (considerable disruptions
to daily life: dangerous to impossible driving conditions,
widespread closures, and disruptions to infrastructure) from the
OH VLY 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
amounts. The D.C/Baltimore area on north to Philly and NYC are
likely to see some inclusion of sleet and potentially some freezing
rain, but it will still result in significant impacts when
accounting for heavy snowfall that is expected to exceed warning
criteria (5-6"). Gusty winds increasing with the developing
surface low off the Mid-Alantic coast may also lead to a brief
period of near-blizzard conditions across eastern New England,
including Boston, late tonight. A reminder that bitterly cold
temperatures will follow in wake of this storm through the middle
of next week throughout the eastern U.S., so snow/sleet impacts
will linger for many days even after precipitation ends.

Freezing Rain...
The most lasting impact will come as a result of significant to
locally catastrophic ice accumulations due to prolonged periods of
freezing rain. Just like the swath of >6" of snowfall, the areal
coverage of impactful freezing rain remains expansive across the
Mid- South, where the event concludes by midday today and a
secondary area east of the Cumberland Gap from northern GA through
central VA and southern MD, including much of the Carolinas. In
these regions, at least 0.25" of total ice is expected to be
widespread, with a more narrow corridor embedded within of at least
an additional 0.5" (30-60%), highest today across the NC Piedmont
into south-central VA. This amount of freezing rain can create
widespread power outages and tree damage, as well as treacherous to
impossible travel at times.

For LA, MS, TN, ice accumulation is "additional" beyond what will
occur before 12Z (6am CST), so local amounts above 1" are actually
expected to be much more widespread than the very low
probabilities suggest for solely today's precipitation. The
greatest additional icing after 12Z today is located across the
Mid- Atlantic, where up to 0.5" is possible. With very cold weather
in place, this will become a life- threatening situation where
freezing rain amounts are highest (including the Lower MS VLY and
Mid-South) with potentially impossible travel due to downed trees
and power lines.

Key Messages for this system are linked below (Key Message 2).
Key messages for the widespread extreme cold are linked below as
well (Key Message 1).

...Great Lakes... Days 2-3...

Broad cyclonic flow will persist across the east, but an embedded
shortwave within this trough will dig out of Alberta Monday night
and then cross the Great Lakes from northwest to southeast during
Tuesday. This will enhance CAA, leading to another round of lake
effect snow (LES), although the duration and intensity of this
event should be modest overall, some moderate accumulations are
still expected beginning D2-3 and lingering beyond this forecast
period. LES from Lake Erie should be minimal as that lake is now
ice covered according to GLERL and should continue to see ice
thicken with very cold temperatures in place, but elsewhere, WPC
probabilities are high for 4+ inches near the Tug Hill Plateau.

Snell/Weiss

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

https://www.wpc.ncep.noaa.gov/key_messages/LatestKeyMessage_1.png

https://www.wpc.ncep.noaa.gov/key_messages/LatestKeyMessage_2.png

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