Updated May 10, 2009
Future updates will only be made when the snow level increases or closures occur related to snow and ice conditions.
Snowfall depth for 2008-2009 winter season
A total of 426 inches of snow fell at Snoqualmie Pass through May 10, 2009, 104.9% of the five-year average.
As the 2008-09 winter season progresses WSDOT asks motorists to be prepared and slow down. For winter driving, remember, Ice and Snow, Take it Slow.
Snoqualmie Pass
Interstate 90 Snoqualmie Pass is a crucial transportation artery carrying passengers and freight across Washington. More than 10 million travelers, including significant commercial traffic, cross Snoqualmie Pass each year. In 2005, the Washington State Legislature funded five miles of improvements for I-90 east of Hyak.
Why was the Pass Closed?
Highway maintenance crews are ready 24 hours a day, seven days a week to treat the roadway and remove snow and ice. There are times when short-term roadway closures are necessary to safely clear incidents and remove snow and ice. As you can see below, avalanche impacts and traffic collisions contribute to most pass closures. Avalanche closures include avalanche control work, natural avalanches, and avalanche danger. Collision closures include traffic collisions, spin outs, blocking vehicles, and more.
Snowfall and avalanche control
When the snow piles up and conditions are right, avalanches result. While Snoqualmie Pass has began to accumulate snowfall, WSDOT’s focus on avalanche control (intentionally triggering an avalanche) minimizes natural avalanches.
Drivers are at risk without a comprehensive program to monitor and bring down the unstable snow pack. The work is usually necessary during times of heavy snowfall. It is critical that avalanche control be done before unstable snow naturally slides. When possible, WSDOT performs avalanche control during periods of light traffic since traffic must be stopped for safety.
Over the past five-year period, Snoqualmie Pass received an average annual snowfall of 406 inches per year. View historical snowfall data (pdf 25kb).