Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
349 PM EDT Wed Oct 29 2025

Valid 00Z Thu Oct 30 2025 - 00Z Sun Nov 02 2025


...Washington Cascades...
Day 3...

Another strong shortwave will lift towards British Columbia late
Friday and Friday night, channeling moisture within a zonal Pacific
jet into the Pacific Northwest. Both IVT and PW anomalies from
NAEFS are progged to exceed the 97th percentile within the CFSR
climatology, suggesting that precipitation may become heavy very
late on D3. However, the accompanying WAA driving this moisture
plume northeastward will surge snow levels to 8000-9000 ft, and any
cold advection associated with a surface front will be delayed
until beyond this forecast period. This should limit appreciable
snowfall
to the northernmost portions of the WA Cascades, with impacts still
expected to remain above pass level through Saturday.

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

Asherman/Weiss