Stevens Pass

Significant snow now blankets much of the mountains.  You can trigger avalanches on steep slopes where the wind has drifted slabs of snow at upper elevations. You can avoid the danger by sticking to wind-sheltered areas and slopes under 35 degrees.

On Monday, an observer reported a small, but long running avalanche, involving loose, uncohesive snow in steep, unsupported terrain at Stevens Pass Resort, SE aspect at 5,400ft. Over the weekend, observers reported numerous avalanches running on layers within the recent snow. Most were small and human-triggered with a few reports of natural avalanches and slides up to size D2. Saturday's avalanches were predominantly wind slabs on leeward slopes. Sunday's reports included a mix of wind slabs and a number of shallow storm slabs on wind-sheltered slopes. 

Since December, 8th the Schmidt Haus recorded over 55" of snow with 4.5" of water equivalent. While the various storm layers bonded quickly, it's worth assessing them before traveling on steep slopes. On slopes over 5,000ft, a stout crust (formed in late November) is at the bottom of the snowpack. The December 8th crust rests just above that and is intermittent up to at least 6,200ft. Observers reported variable tests on both crusts including some sudden planar results. While we haven't confirmed avalanches on these crusts, they're worth keeping an eye on.

Preliminary Report: On Saturday morning, December 11, a party of six backcountry tourers were traveling uphill in a closed section of the Crystal Mountain Ski Area known as Silver Basin. The party triggered a large avalanche on an NE to E facing slope at approximately 6600’. While all members of the party were initially caught, four were fully buried. A nearby party of two witnessed the event and immediately assisted in the rescue. Crystal Mountain Ski Patrol was also notified and responded to the scene. Unfortunately, one of the fully buried victims did not survive. NWAC and Crystal Mountain Ski Patrol will collaborate to conduct an investigation. Our deepest condolences to the family, friends, and community.  SS-ASu-R3-D2.5-U; Crown Depth: estimated 2’ deep.

Uphill travel reminder: Check in with your local ski area this weekend regarding terrain access and parking updates. For the SPMR uphill hotline call 206-812-7847. Closed ski areas often share a similar snowpack and avalanche hazard as the surrounding backcountry. You may also encounter other hazards like active avalanche mitigation, unmarked obstacles, snowmobiles, groomers, and other heavy equipment as ski areas prepare to open. Be prepared to make your own assessments and handle emergency situations.