FOUS11 KWBC 200912
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
412 AM EST Fri Feb 20 2026

Valid 12Z Fri Feb 20 2026 - 12Z Mon Feb 23 2026

...West Coast... Days 2/3...

Cold core low shifts south from the Gulf of Alaska today, stalling
well off the WA/OR coast Saturday into next week. Pacific moisture
(not too anomalous with PW below 1" streams inland over the
entirety of the Pacific Northwest Friday night/Saturday then again
Sunday through at least Monday. Snow levels rise to 3000 to 4000ft
Saturday morning, then 5000 to 6000ft (4000ft in Washington)
Sunday. Both Days 2 and 3 snow probs for >6" are 50-80% for the
Cascades and Shasta/Siskiyou. Most of the heavy snow will occur
above the major mountain passes.

...Southern Rockies... Day 1...

Trough axis pushing into southwest Utah this morning shifts across
the southern Rockies today and Kansas this evening. Pacific
moisture streaming ahead of this trough will bring welcome mountain
snow to western slopes of CO ranges today with the San Juans and
Elk mtns most impacted. Day 1 snow probs for >8" are 50-80% there
and 40-70% in the Park Range, Sangre de Cristos, and other western CO ranges.

...Upper Midwest... Days 1-2...

Mid-level low over eastern IA will shift across southern MI today
as a separate low over the Boundary Waters of MN shifting
northwest. Heavy snow bands over central/eastern IA and western WI
will continue to pivot north to south up over the U.P. where lake
enhanced snow lingers through tonight. Day 1 (after 12Z) snow
probs for >8" are 40-70% for the Keweenaw Peninsula through the Huron Mtns.

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

Mid-level low shifting over lower Michigan today will track across
NY and southern New England tonight. Surface low development occurs
downstream this evening, crossing the 70/40 Benchmark this evening.
Warm air advection precip pushing into central PA will continue to
lift over NY and New England through this evening.

Warm nose progression pushes into Mass today, but with wintry mix
south from there and heavy snow north. Day 1 snow probs for >8" are
40-80% for the Adirondacks, Greens, and southern NH. Day 1 ice
probs for >0.1" are 40-60% for the Catskills, Mohawk Valley,
Litchfield Hills into the Berkshires with some sleet along the
northern extent of this freezing rain zone.

...Central Appalachians and Mid-Atlantic... Day 3...

*** Nor'easter develops off Mid-Atlantic Coast late Sunday with
 impacts in the Northeast through Monday ***

Complex phasing is expected to result in coastal low development
off the Mid-Atlantic coast later Sunday with rapid intensification
as it shifts northeast Sunday night/Monday. Guidance is somewhat
coming into consensus with a surface low track east of where the
GFS and west of where the EC have been. The preferred track remains
with the EC-AIFS which the 00Z run did nudge south a bit for Sunday
night. The extent of the precip shield will be critical to heavy
snow banding on the NW/W side of the low. Non-uniform precip shield
depiction from guidance such as the EC is likely given the complex
interaction of mid-level and low level low centers. The Day 3 snow
probs for >6" are 40-60% for central MD through southeast PA,
southern NJ and much of the Delmarva Peninsula. The rapid low
development and approach of rather strong surface high pressure
to Ontario will lead to a sprawling wind field over the eastern
U.S. which will enhance snow impacts under heavy TROWAL bands.
Please stay tuned for further details.

The greater confidence is for upslope snow on the central
Appalachians in NW flow on the back side of the system Sunday
night. Great Lakes moisture encounters the topographical lift with
Day 3 snow probs for >6" 40-80% above about 1500ft to the Allegheny
Front in WV and far western MD.

Jackson

$$
--- SBBSecho 3.28-Linux
 * Origin: Capitol City Online (618:250/1)