Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
314 PM EDT Tue Apr 22 2025

Valid 00Z Wed Apr 23 2025 - 00Z Sat Apr 26 2025


...Northern Rockies...
Days 1-2...

Shortwave moving into/through Oregon this evening/overnight will
spread a new round of generally light snow across southwestern MT
and northwestern WY as it deepens over the northern Great Basin.
Upper jet will be positioned over the northern Plains, aiding in
ascent over the region where temperatures are mostly mild,
confining snowfall to areas above 7000ft or so. This feature will
weaken as it pushes through Idaho and into western Montana Thursday
night with snow tapering off by Friday morning. WPC probabilities
for at least 8 inches of snow are moderate (40-70%) over the
Absarokas and Wind River ranges and generally less than 50% over
the Bighorns.


...Northern California...
Day 3...

A deep upper trough in the northeastern Pacific will dig
and deepen into a closed low just west of NorCal by Friday, sending
in some moisture to the region. Snow levels will start high,
confining generally light snow to areas above 7000ft where WPC
probabilities are low (10-40%) through 00Z Sat. More snow is
expected thereafter.


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

Fracasso