Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

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

Wind slabs will remain reactive Wednesday. Uncommon SE winds have distributed snow in unusual locations-use visual clues to identify wind affected slopes.  Choose slopes under 35 degrees where you see textured snow, fresh drifts, or deeper areas of unconsolidated snow.

Avalanche problems

  • Wind Slabs

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

    Fresh and sensitive wind slabs formed Tuesday night and continue to grow into Wednesday. Due to the direction and consistent nature of the winds in this storm, you should find the majority of slabs on SW-N-NE aspects. Strong winds, particularly near the crest, created a more erratic loading pattern and scoured ridgelines. In some locations, these slabs may have developed over weak snow grains buried Saturday night. As a result, avalanches may trigger easily, propagate widely, and run quickly. With the potential for sensitive slabs in unusual locations, use visual clues such as fresh cornices and smooth drifts to identity wind-loaded features. Do not rely on familiar patterns as you travel. Take note of changing snow conditions as you approach new aspects and as you gain elevation. When you suspect wind loaded snow, go around and choose lower angled, less wind affected, or more treed slopes to avoid the wind slab problem.

    (1/23/2021) Small and shallow wind pockets were found to be reactive, producing long shooting cracks in the Crystal backcountry on 1/23. This isolated slab failed on weak facets.

Avalanche Discussion

Uncommon SE winds accompanied Tuesday night's snow. As a result, wind slabs of varying thickness, firmness, and reactivity exist depending on your location in the West South zone. Another less significant storm approaches Wednesday night but should follow the same pattern and continue to deepen slabs above a relatively weak snow surface and favor unusual locations and aspects. Sugary facets, feathery surface hoar, and a thin sun crust were all observed and potentially buried on Saturday (1/23). Wednesday evening, we know these weak layers exist. As slabs grow and stiffen, we may see a more active period of avalanche activity involving the recent snow. 

The recent snow sits above a very prominent and often icy (1/13) crust. Away of wind-affected areas, expect very unconsolidated and poorly bonded snow. As a result, you may trigger small loose/sluff avalanches. Even small slides can harm you if they knock you over a cliff or into an open creek. 

While travel conditions continue to improve with the recent snow, variable and sometimes icy surfaces still remain. Expect firm slopes in forested areas and along wind-scoured ridges. 

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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