Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
415 PM EDT Wed Nov 03 2021

Valid 00Z Thu Nov 04 2021 - 00Z Sun Nov 07 2021


...Washington...
Days 1-3...

A parade of shortwave troughs through the Pacific Northwest
beginning tonight through the weekend will bring favorable forcing
for ascent and moisture transport to produce widespread
precipitation across favored upslope regions of the WA Olympics
and Cascades. Snow levels initially will be high (7000+ ft) but
after the initial shortwave trough passage, snow levels will
gradually drop to around 3000-4000 ft. WPC probabilities for 4
inches increase through the period, starting off at moderate/high
for just the highest peaks of the Cascades. By Day 2 and Day 3,
the 4 inch probabilities increase and spread across more of the
Cascades and into the Olympics. By Day 3, moderate probabilities
for 6 inches exist for the high peaks of the Olympics and northern
Cascades.


For Days 1-3, the probability of significant icing is less than 10
percent.

Taylor