Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

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Out of date — this forecast expired 3 years ago.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

Highlights

It will take more than a little bit of cooler weather to bring an end to the wet avalanche concerns. Isolated natural large avalanches could occur as snow sheds from rocky and complex terrain. Stay off of steep soggy slopes and limit any time you spend beneath them.

Avalanche problems

  • Wet Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2.5

    While the bulk of the rain will have passed by Monday morning, wet avalanches may continue to occur. Some of these potential slides could be harder to trigger, but if they get rolling they will entrain plenty of wet heavy snow and act more like a bulldozer plowing down the hillside. This isn’t an avalanche problem to try and manage. Best to just stay out of its way and let the snowpack deal with the sudden switch from winter to spring. 

    Wet slabs are notoriously hard to predict, but the ongoing rain falling on a cold, dry, layered snowpack is a pretty good recipe. You could also see natural loose wet, glide, and cornice avalanches with these conditions. Ultimately the travel advice is the same; seek out terrain away from steep open areas.

    (1/15/2023) Example: Wet avalanche debris from a rain even earlier this winter.  Photo: Dallas Glass

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    Near the tops of the highest peaks around the Pass, you’ll probably encounter drier conditions. While this warmer snow should bond pretty well to the underlying old surface, be leery of places where the wind formed slightly deeper and firmer slabs. Textured surfaces and sharp cornices can help you anticipate these wind-loaded pockets. Pay attention near ridgelines and in the tops of chutes where you’re most likely to trigger one of these small avalanches.

    (3/24/2023)

    Example: A shallow human-triggered slab in a confined chute on Mount Snoqualmie. 

    Photo: Jourdan Harvey

Avalanche Discussion

An atmospheric river continues to take aim at the Pacific Northwest Sunday night and into Monday. Even though temperatures will cool slightly, the warm wet weather is far from over. While not a huge storm by Cascade standards, this is a pretty big change for what was a very cold, dry, and layered snowpack. 

Observations from during this storm were limited due to the nasty weather. As of Sunday afternoon, the Pass had received around an inch of precipitation, with rain above the top of Alpental (~5500ft). We don’t know if this resulted in a widespread avalanche cycle or not. Let us know what you find as you travel on Monday.

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