Bulletin d’avalanche

Snoqualmie Pass

Northwest Avalanche Center
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Danger d’avalanche

Sun
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
2 · Modéré
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Périmé — ce bulletin a expiré 6 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Windy conditions and poor visibility could make travel in the mountains challenging Saturday. When you see blowing snow, anticipate potential avalanches on slopes where it deposits. Steer around any steep open areas where you suspect wind loading.

Problèmes avalancheux

  • Wind Slabs

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

    This storm doesn’t appear to produce very much snow, however, it looks quite windy. You may find erratic and unusual loading patterns with new wind slabs on a variety of aspects, well below ridgeline, and along the sides of mid-slope features. These new slabs could form on several different snow surfaces including smooth ice and weak soft snow. This may allow them to trigger easily underneath you. Since visibility could be terrible, don’t rely entirely on snow surface clues to show you which slopes are loaded. Instead, pay attention to the wind direction and blowing snow. Anticipate which aspects and features could hold wind slabs. Steer around steep open and convex slopes if you suspect wind loading. You may find larger and more dangerous avalanches at higher elevations and later in the day. 

    In more sheltered areas, a cooling trend should create a right-side-up snowpack structure and you may see loose dry avalanches. These could run quickly if they occur over the icy crust.

    (12/23/2020) Blowing snow from moderate southeasterly winds was forming thin new wind slabs. Chair Peak, 5200' N aspect.

Avalanche Discussion

A very prominent icy crust (12/21) formed during last weekend’s rain events. This layer should limit any avalanche activity to the snow above. Windy conditions over the past several days created a variety of snow surfaces including soft weak snow, wind-scoured ice, breakable crust, and firm wind drifts. You may experience the new snow reacting differently depending on which surfaces it accumulates. In places where the icy layer is exposed or near the surface, a simple slip could easily turn into an uncontrolled fall. Use caution if you travel over these slippery slopes. 

At lower elevations, early season conditions still exist with numerous obstacles, open creeks, and holes in the snowpack. Give yourself extra time to deal with these hazards. 

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.

Régions couvertes