Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
201 PM EDT Tue Apr 29 2025

Valid 00Z Wed Apr 30 2025 - 00Z Sat May 03 2025


...Northern/Central Rockies...
Days 1-2...

Positively-tilted trough over southwestern Canada/northern Divide
this evening will carry a cold front through the region with colder
air in its wake and lowering snow levels. Precipitation will
translate from northwest to southeast Days 1-2 from southwestern MT
through Wyoming then into the CO Rockies. By Wednesday evening,
the trough will moving into the High Plains as heights rebound into
Day 3, ending any snowfall over the region. Snow levels will start
around 8000ft near/ahead of the cold front then drop to
6500-7000ft during the morning hours behind the front, only to rise
again over 7000ft during the day. This will confine the most snow
to the mountain ranges like the Absarokas, Tetons/Wind River,
Bighorns, and CO Rockies. WPC probabilities for at least 8 inches
of snow for this period are at least 50% above 10,000ft or so.

The probability of at least 4 inches of snow on Day 3 is less than
10%.

The probability of at least 0.10" of freezing rain across CONUS is
less than 10%.


Fracasso