Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
330 AM EDT Fri Oct 25 2024

Valid 12Z Fri Oct 25 2024 - 12Z Mon Oct 28 2024


...Pacific Northwest...
Day 3...

Upper level ridging will give way to a broad upper trough, carved
out by a series of shortwaves moving south of a low moving into
British Columbia. This will support the return of unsettled weather
and falling snow levels in the wake of a strong cold front moving
from the Northwest into the northern Rockies on Sunday. Strong mid-
to-upper level forcing and a shot of deeper moisture are expected
to generate some of the heaviest precipitation across western
Washington and Oregon Saturday night into Sunday morning. However,
with snow levels above 6000 ft in most locations, winter weather
impacts will be limited. Snow levels are expected to steadily drop
through Sunday, reaching to around 4500 ft in the northern Cascades
by Monday morning. Conditions will remain unsettled as onshore
flow persists. However, WPC probabilities indicate that most
significant snow accumulations will remain above pass level.

The probability of significant ice across the CONUS is less than
10 percent.

Pereira