Avalanche forecast

Summit Lake

Chugach National Forest Avalanche Center
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Avalanche danger

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

Continued strong winds at upper elevations will form fresh wind slabs up to a foot deep. Human triggered avalanches will be possible on recently wind loaded slopes. Several buried weak layers exist in the snowpack, but due to the lack of recent snowfall, we think the avalanches on these layers are unlikely. Glide avalanches have been observed across the region this week and we recommend avoiding glide cracks. 

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

    Yesterday's storm was more blow than snow, with ridgetop winds averaging 20 to 30 mph from the southeast and gusts up to 60 mph. Girdwood and Seward were favored with 2-5" of new snow while Turnagain Pass and Summit Lake only received a trace to 1" of new snow.

    Continued 20-30 mph southeast ridgetop winds will form fresh wind slabs at upper elevations today. Even though the snow surface is already wind affected at upper elevations, strong winds can always find more snow to transport onto leeward slopes. You can identify fresh wind slabs by looking for slopes with active wind transport, hollow feeling pillows of snow, and shooting cracks on the snow surface. Probing with a ski pole, using hand pits, or checking for wind slabs on small test slopes can be useful ways to assess the distribution and sensitivity of wind slabs before entering steeper terrain.

    Glide avalanches and glide cracks have been observed across the region in the past two weeks. These are unpredictable and can cause very large and destructive avalanches, so we recommend avoiding spending time underneath open glide cracks. 

    Cornices have also grown very large at this point in the season and can fail naturally during periods of active wind loading. Try to avoid traveling underneath cornices while they are being loaded and give them a wide berth when traveling along ridgelines. 

    Snowfall forecast for Saturday from NWS Anchorage.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    2–3

    The lack of new snow expected in Summit Lake today will limit the likelihood of buried weak layers becoming active again. The most concerning areas for larger avalanches releasing on weak layers 2-4'+ deep are high elevation start zones being actively wind loaded. Deep persistent avalanches are often triggered from a thin spot in the snowpack connected to an adjacent start zone. As always with persistent weak layers, the best way to avoid them is to stick to lower angle terrain. 

    Several buried weak layers exist in the Summit Lake snowpack which could become more sensitive due to wind loading.

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