Bulletin d’avalanche

West Slopes North

Northwest Avalanche Center
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Danger d’avalanche

Sun
Alpin
3 · Marqué
Limite forestière
2 · Modéré
Sous la limite
1 · Faible
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Points saillants

It is likely that you can trigger an avalanche in subtly wind affected, low-density snow on Saturday. It may be a challenge to identify as the snow could be very soft, but the main clues to pay attention to are heavier feeling snow, seeing wind-textured features, and noticing long, shooting cracks as you move through the snow. If you find any of these indicators, or see any recent sign of avalanches, steer clear of nearby steep slopes. 

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    1–2

    We received a report of a large (D2) human-triggered wind slab avalanche in the Baker backcountry on Friday. Companions were below, and had to quickly move out of the way to avoid getting caught in the avalanche as it ran down the slope. Only a few additional inches of snow are forecasted Friday night, but with light to moderate winds subtly shifting snow, it is likely that you could trigger avalanches on Saturday. These drifts could remain very soft, not the obvious stiff features that you may consider your average wind slab. You're most likely to find reactive snow in areas where drifts form, such as around rocky outcroppings, beneath ridges, in gullies, or on steep rollovers. Expect to find it easier to trigger an avalanche as you gain elevation. Uncertainty exists as to how reactive these newer slabs may be.  If you have any doubts, stick to slopes less than 35 degrees.  

    (12/2/2022)

    A skier triggered D2 (large) avalanche which occurred in the Baker backcountry on Friday. It appears to be a wind slab in very steep (>40deg), committing terrain. It is unknown whether the avalanche occurred only in new snow, or also involved older layers. 

    Photo: John Minier- Baker Mtn Guides

Avalanche Discussion

In non wind-affected areas you might see or trigger shallow surface sluffs, or dry loose avalanches. Make sure to stay aware of ones that may be triggered by you if you're on a steep slope. Temperatures are expected to warm throughout the day, and if skies clear you may see wet loose avalanches on sunny slopes in the afternoon. 

A few smaller snowfalls occurred over the last several days, and people have been excited to get out and enjoy the deepening snowpack with the low-density snow on top. This weekend we expect a lot of people will get out in the backcountry.  It's not open season. Make sure to start on smaller slopes and evaluate each new feature before you head out onto it. Have an escape route planned. Try to avoid being on a slope with other people.  Even a small avalanche could be dangerous if there is a terrain trap beneath you. Make sure to evaluate your surroundings constantly, whether traveling up, down, or across a slope and quickly change your plans when you encounter differences from what you expect to see. 

We've generally found stable snow in this zone, aside from newer surface instabilities. However, we don't have a clear picture about the entire snowpack yet, and in some areas throughout the Cascades, weaker snow has been found around crusts near the ground. We received one report of a whumph in the Baker backcountry on Wednesday, and there are some locations where this weak snow may exist. Keep this in mind as you travel in the backcountry.  There are still higher risks of hitting trees and rocks during your travels, as we're not seeing a really deep coating of snow yet. Information about the snowpack is limited, so if you are out in the mountains, let us know what you encounter by submitting an observation. 

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