Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Wed
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Out of date — this forecast expired 3 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

An atmospheric river will continue to soak our early-season snowpack with rain at Snoqualmie Pass through Tuesday. The height of natural avalanche activity is expected to have passed, but that doesn’t mean it’s finished. Be cautious on slopes over 35 degrees, where wet avalanches are more likely.  

Avalanche problems

  • Wet Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2.5

    You’ll be hard-pressed to find dry snow anywhere in our zone by the time day breaks on Tuesday. Expect a rain-soaked, punchy snowpack ripe for human-triggered avalanches. We anticipate natural activity to diminish but not be eliminated. Slabs will be more likely at upper elevations and could run on the 11/30 interface. Slides could fail on or near the ground in isolated locations as liquid water fully saturates the snowpack. Be cautious of large open slopes where larger avalanches can start, run, or stop. Of course, loose avalanches will also be a concern. Any slope over 35 degrees could produce a consequential avalanche if terrain traps are involved.

    (1/13/2023)

    Example: Wet avalanches near ridgeline from an atmospheric river last season.

    Photo: Trevor Kostanich

Avalanche Discussion

Monday night will be the main event in our multi-day rain cycle. By the time Tuesday morning rolls around, we anticipate that many slopes will have shed their instabilities. This thinking allowed us to drop the hazard level. That doesn’t mean that Tuesday won’t be dangerous. The heavy rain will continue destabilizing the snowpack, and avalanches will occur. 

Apart from lingering natural avalanches and human-triggered slides, a whole mess of wet snow-related problems likely await you in the mountains. Unconsolidated wet snow makes for difficult and dangerous travel conditions. Raging creeks, holes, exposed natural hazards such as logs and boulders, and avalanche debris will be commonplace across the landscape.

We’ve had a crazy few days weather-wise greatly stressing the snowpack. After receiving multiple feet of snow on top of an observed weak early-season snowpack, we’ll have added 6-7 inches of rain by the time Tuesday wraps up. Overall, it likely won’t be a pleasant day to be outside playing in the mountains. Give the snowpack the time it needs to adjust and wait for a more pleasant day to head out and explore.

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