Avalanche forecast

Summit Lake

Chugach National Forest Avalanche Center
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Avalanche danger

Thu
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Highlights

The avalanche danger will start out MODERATE and rise to CONSIDERABLE as the air temperature and sun melt the snow surface. Numerous new glide avalanche and wet avalanches observed within the last 2 days are making these problems the biggest concern today. These avalanches are very dangerous and it's best to avoid being underneath any glide crack right now. Wet loose avalanches are occurring naturally and are growing in size with each passing warm day and more dangerous wet slabs are becoming possible. As surface crusts break down, or where they don't exist, a person could also trigger a large avalanche on a layer of buried surface hoar that is about 1' deep in Summit Lake. There is a lot of uncertainty with the timing of dangerous conditions and these problems can be avoided by choosing low angle slopes. 

Avalanche problems

  • Glide Cracks

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

    Recent Avalanches: Numerous reports came in yesterday evening of new glide and wet avalanches from the last 2 days. Many of these were in the Turnagain Pass zone, but activity has been elevated in the Summit Lake zone as well.

    All the activity in the afternoon the last few days, and another warm day forecast today, means avalanche conditions will be dangerous this afternoon, or even this morning, if there are places that didn't freeze hard last night. High clouds are forecast to come in this afternoon, which could cool things off and make these problems less likely, but that depends on many factors like air temperature, timing of clouds, and potential greenhousing. Glide avalanches take the snowpack to the ground and have been running below treeline so it is best to completely avoid being underneath a glide crack right now. 

    Wet loose avalanches have been releasing naturally and will be more likely for a person to trigger as the snowpack warms through the day. These avalanches could be bigger today than they have been and they have the potential to trigger a larger slab avalanche. A scary sign of a wet slab collapse was observed just below 2.000' on a southwest aspect of Center Ridge yesterday. Although this occurred in Turnagain Pass conditions have been similar in Summit Lake. Even relatively small wet loose avalanches can be difficult to escape and the consequences of being caught in a wet slab are severe. If your boot is sinking to your mid-calf it's time to look for colder snow. Although this could lead you to problem 2 described below.

    Cornices are also failing in the heat of the day. Some cornice fall has triggered large avalanches below, so this is another reason to avoid being underneath steep slopes in the afternoon. 

    (3/31/2025)

    New glide avalanche on the east side of Summit Mountain and the north wind blowing snow off the ridgeline.

    Photo: Mik Dalpes

  • Persistent Slabs

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

    Although this has moved to problem 2 with all the wet snow problems that are occurring, we still think a person could trigger a large avalanche on the layer of buried surface hoar that is about 1' deep in Summit Lake. We have some uncertainty as to how likely it is for a person to trigger an avalanche on this layer, but the history of this layer's behavior has made it difficult to trust in Turnagain Pass. It has failed after there are many tracks on a slope, and it has been triggered remotely and from low angle terrain. 

    On mornings when a stout crust has formed, conditions are generally safer as this crust can protect us from impacting the buried surface hoar and causing it's collapse. However, the timing of crust break down is tricky and this layer has shown the potential to cause an avalanche as recently as March 25 on Raven's Ridge where forecasters experienced the red flags of cracking and collapsing. 

    If you are choosing to ride steep slopes look for small terrain features rather than large open bowls. Also ensure there are no terrain traps below like gullies or depressions where the snow could pile up and make a rescue difficult. 

    (3/25/2025)

    John's geometrically perfect ECT column. The surface hoar layer suddenly collapsed and slid toward us. 

    Photo: Daniel Krueger

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