Avalanche forecast

West Slopes Central

Northwest Avalanche Center
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Avalanche danger

Sat
Alpine
4 · High
Treeline
4 · High
Below
3 · Considerable
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Out of date — this forecast expired 5 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Very dangerous avalanche conditions exist as it snows and strong winds continue on Friday. Expect to find reactive wind slabs which may be found further downslope than they might normally exist.  Avoid slopes greater than 35 degrees, and stay out of the areas beneath steep slopes as well.

Avalanche problems

  • Deep Persistent Slabs

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

    Stay alert for deep persistent slabs as more weight (snow) continues to load them. Chances that you will trigger an avalanche on this layer are unlikely, however with the added weight of a fresh wind slab on an upper elevation slope an avalanche occurring is not out of the question. Keep this in mind, especially when you approach the runouts of large avalanche paths as this storm is actively loading the start zone with thick deposits. Stay out of the steep start zones as well. 

    (2/24/2021) Evergreen Mountain southwest face. This avalanche may have stepped down to the mid Jan persisten weak layer.

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    2

    Wind slab avalanches are your biggest concern on Friday. Around two feet of snow fell in the last 36 hours, and winds were strong, redistributing the fresh snow into touchy slabs. In some areas, these could fail naturally- especially in gullies, beneath rock bands, below cornices (which are getting very large) and under ridgelines. Your added weight makes an avalanche occurring on steep slopes very likely.  

    Because of the strong wind, you might find some areas stripped back to firm surfaces, while other slopes and features have thick pillows of snow up to several feet deep. You may find slabs in unusual locations, such as lower on a slope than you would normally suspect. There are a number of underlying layers of concern which avalanches could fail on, such as a sun crust from Wednesday’s intense sun on steep southerly slopes, or a layer of graupel in other areas. You may find slabs 6 inches to several feet thick. In non-wind loaded steep areas expect to encounter loose dry avalanches, or possibly storm slabs in the new snow. Due to this uncertainty stick to slopes less than 35 degrees on Friday, and avoid lower angle terrain which is beneath avalanche paths as well.

    (2/24/2021) Silica Peak area. Small slabs stepping down to deeper slabs, with small loose dry avalanches on top.

Avalanche Discussion

Earlier this week a large storm and extensive avalanche cycle ran its course throughout the Cascades. Very large natural avalanches occurred in the West Central zone, which you can see in the media strip below. After an epic bluebird powder day on Wednesday we’ve jumped right back into another storm. The short break helped stabilize new snow instabilities, but weaknesses are still a concern in the top several feet of snow. This is especially the case with all our recent snow that redistributed in the last 36 hours with wind. Keep alert so you don’t get caught in any avalanches as the storm winds down.

During the ongoing Covid-19 pandemic, continue to follow the latest guidance from local, state, and federal health officials. Avoid unnecessary risks that could impact first responders and stress medical resources.  Wear a mask when appropriate, practice social distancing, and consider recreating closer to home.

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