FOUS11 KWBC 220932
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
432 AM EST Sun Feb 22 2026

Valid 12Z Sun Feb 22 2026 - 12Z Wed Feb 25 2026

...Central Appalachians, Mid-Atlantic, through Northeast... Days 1-2...

*** Nor'Easter rapidly develops today as it slowly shifts north just
 off the Mid-Atlantic Coast. Heavy snow and blizzard conditions 
 are expected for the Delmarva through the Northeast Urban Corridor
 through eastern New England through Monday. ***

Northern stream mid-level trough axis is over St. Louis while
a southern stream wave in the right entrance region of the SWly 
jet is allowing surface cyclogenesis over the Carolina Coast. These
features phase this morning, the jet shifts east, bringing the
surface low into the left exit of the jet stream, promoting rapid 
low development north of Cape Hatteras. 1050mb surface high 
pressure approaches Ontario tonight, setting up a great pressure 
gradient across the Great Lakes and Northeast. By this afternoon,
the deepening low off the Delmarva begins drawing cold air in from
the NW with low level fgen banding allowing snow accum across the 
Mid-Atlantic (from the morning rain to higher elevation snow). Snow
rates really increase this evening over the Delmarva/NJ and NYC 
from the combo of further low development and nocturnal trends with
00Z HREF mean snow rates of 1"/hr over this area by 00Z with 
localized 2"/hr rates in NJ by midnight. Late night snow rates 
further increase, exceeding 2.5"/hr over Long Island before 
shifting to southeast New England by 09Z. Day 1 snow probs for >12"
are 70-90% from the MD part of the Delmarva through southeast 
Mass. Day 1 snow probs for >24% are 50% for the central Jersey 
Shore. Probs for >6" greater than 50% are over the Blue Ridge, 
north/east of the Potomac River in central/southern Maryland, 
across eastern PA and the Hudson Valley.

Event peak snow rates per the HREF are 3"/hr early Monday, though 
the very high winds (with gusts potentially to 70mph) will limit 
the SLR, so that may not be realized, but it'll be quite impactful
snow banding with oceanic enhancement. The low then pivots to 
Nova Scotia with rates of 1-2"/hr through Monday afternoon. Monday
evening north flow from the Gulf of Maine should allow a pivoting
band of ocean enhanced snow into southeast Mass/Cape Cod further
adding to the historic snow. Day 2 snow probs for >12" are 50-70%
over eastern Mass and just off the Maine coast with 50% probs for
>6" from southern NH through eastern Maine and down through eastern CT.

Upslope snow through the central Apps begins this afternoon, 
continuing through Monday evening. Snow rates generally stay below
1"/hr, but the prolonged duration leads to some significant snow
fall. Day 1 snow probs for >8" are 50-80% from the Laurels of PA
through the Allegheny Plateau of central WV.

...Cascades and Northern Rockies... Days 1-3...

Sprawling deep low lingers well off the WA coast today which
directs Pacific moisture across the Northwest CONUS. This low then
shears into a zonally oriented trough Monday which directs an 
atmospheric river (AR) into OR later Monday before shunting south 
through northern CA Monday night/Tuesday. 

Snow levels rise today to 3500ft in the WA Cascades, 5000-6000ft 
in OR, and 6500ft in far northern CA. Day 1 snow probs for >6" are
40-80% in the WA Cascades (above pass level) and the highest OR/CA Cascades.

A tighter baroclinic zone sets up Monday with snow levels dropping
to around 2500ft at Snoqualmie Pass WA and to around 4000ft in
northwest MT while rising above 7000/8000ft in the core of the AR 
in OR. Day 2 snow probs for >6" are 50% at pass level in the WA
Cascades and for the ranges of northwest MT.

The southward shift in the AR through Tuesday brings heavy precip
to northern portions of CA and the Great Basin with CA snow levels
over 9000ft with no snow impacts. Snow levels are closer to 7000ft
in NW WY and central ID where Day 3 snow probs are 50-80%.

...Great Lakes... Days 1/2...

Inverted trough extending northwest from low over Lake Huron
maintains NNWly flow and strong cold air advection over Lakes
Superior and Michigan today. This expands east across Lake Erie
tonight into Monday as the Nor'easter develops off the Mid- 
Atlantic coast. Day 1 snow probs for >4" are 40-70% over the 
Porcupine and Huron Mtns as well as over far SW MI and northern IN.
Day 1.5 snow probs for >4" are 40-70% southeast of Lake Erie in
northeast OH, Erie Co PA, and Chautauqua Co NY. 

Day 3...

An Alberta Clipper shift ESE from northern MN through MI Tuesday
before reaching Upstate NY Tuesday night. Warm air advection ahead
of the surface low will be into an Arctic airmass with plenty of
DGZ available for snow crystal growth. Moderate snow rates from
Lake Michigan enhancement can be expected in the eastern U.P. where
Day 3 snow probs for >6" are 40-60%. LES begins on the back side of
the clipper Tuesday night off Lake Superior, spreading across the
Great Lakes then Wednesday. 

Jackson

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

https://www.wpc.ncep.noaa.gov/key_messages/La...

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