The Interstate 90 stretch through Snoqualmie Pass is the most heavily trafficked east-west highway in Washington state. More than 10 million travelers cross the pass each year. At an elevation of 3,022 feet, it is open year-round unless heavy snow forces a closure.
During the summer months, average maximum temperatures in Snoqualmie Pass range from the low 60s to the low 70s with minimum temperatures in the 40s. In the winter, average maximum temperatures are in the 30s and minimums in the 20s.
From 1949 through 2009, the average annual snowfall in Snoqualmie Pass was 436.99 inches according to Washington State Department of Transportation data. The heaviest snows occurred mainly in December and January. During the 2009-2010 winter season 296 inches of snow fell at Snoqualmie Pass.
Crews are always on stand-by to remove snow and ice from the highway. Interstate 90 through Snoqualmie Pass may be temporarily closed for the removal of snow and ice and to clear accidents. Avalanches and motor vehicle collisions cause most of the closures.
If you are traveling through Snoqualmie Pass in the winter, obtain an up-to-date weather report. Heavy snows may cause a highway closure.
