Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
453 PM EDT Mon Apr 25 2022

Valid 00Z Tue Apr 26 2022 - 00Z Fri Apr 29 2022


...Pacific Northwest...
Days 1-3...

Height falls and increased moisture will bring renewed chances for
snow for the elevations generally above 3000-4000 ft across the
WA/OR Cascades into the Clearwater Mountains of ID late tonight
through the first half of Tuesday. For the Olympics and WA
Cascades, WPC probabilities for 4 inches are slight to moderate
(20-40 percent) while for the Clearwater Mountains, probabilities
are above 60 percent for the highest peaks. Isolated totals above
8 inches are possible.


...Northeast...
Day 3...
Shortwave energy will deepen as it crosses the Great Lakes tonight
into Tuesday and gradually takes on a negative tilt as it swings
over the Northeast Wednesday night into Thursday. As a result, a
surface low is forecast to along the existing frontal boundary
offshore and deepen before approaching Nova Scotia. Moisture
thrown back into the Northeast will interact with the favorable
forcing for ascent to produce higher elevation snow across mainly
the interior sections of New England. The system is expected to
occlude Thursday which could keep wrap around snow showers
lingering across northern Maine where some of the guidance is
bullish with totals. The latest WPC probabilities for 4 inches are
40 to 60 percent over extreme northern NH and northern ME.


For days 1-3, the probability of significant icing greater than
0.25 inches is less than 10 percent.


Taylor