Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
2 · Moderate
Treeline
1 · Low
Below
1 · Low
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Highlights

A short-lived storm should impact Snoqualmie Pass on Saturday bringing cooling temperatures, light snowfall, and windy conditions. As you ascend in elevation, look for wind-drifted piles of unstable snow to steer around. They should be lurking on the leeward side of ridgelines or in confined chutes and gullies. 

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    Keep an eye out for wind-loaded features near ridgelines, rocky outcrops, confined gullies, or on convex slopes where you’re more likely to trigger an avalanche on Saturday. Shifting wind directions could result in Wind Slabs developing on different aspects than what you may be used to. Look for them on reverse aspects or cross-loaded mid-slope features by using visual clues such as identifying smooth pillow-like piles of snow or areas that look “fat”. Actively blowing snow, fresh cornices, or drifts behind objects can help you identify potential Wind Slab locations. If you suspect a feature to be wind-loaded, best to just steer around it at this time.

Avalanche Discussion

The Pass picked up around 6 inches of new snow at upper elevations on Friday and we’re expecting to squeeze out another few during the day on Saturday. Winds should ramp up and change direction later in the day, ushering in an east wind event and transporting snow into new drifts.

Several avalanche professionals and Alpental Pro Patrol reported an unforeseen Wet Loose cycle on Friday as the sun came out and destabilized the newly fallen snow. In many areas, these small avalanches were using a sun crust that formed on Thursday as a bed surface, allowing some to run far distances. This small cycle should help mute avalanche activity on Saturday at mid to lower elevations, but may not totally eliminate it. We do not have any reports of buried weak snow at the 1/26 interface at this time.

While the upper snowpack still contains several older interfaces (1/21, 1/18), it’s generally strong, well-settled, and should handle this new storm load. We expect any slide to break at or above the 1/26 interface, particularly where the crust exists. Prior to Friday's storm, 1.5-2 ft of snow sat over the very stout and prominent MLK crust. Use this layer to target your observation on the upper snowpack.

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