Bulletin d’avalanche

Mount Shasta

Mount Shasta Avalanche Center
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Danger d’avalanche

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

Points saillants

Stormy weather has arrived, increasing avalanche danger on all north, east, and south aspects near and above treeline due to new wind slab formation. Evaluate snow carefully and exercise caution in terrain steeper than 30 degrees. Focused assessments and cautious terrain choices are key to staying safe today.

Problèmes avalancheux

  • Wind Slabs

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

    As snow and wind impact the forecast zone, newly forming wind slabs will be the primary concern, especially near and above treeline on leeward aspects. Winds will shift from southwest to northwest throughout the day, loading snow onto north, east, and south aspects, with east aspects receiving the most loading. Caution is advised around the downwind sides of ridgelines, beneath large rock outcroppings, and the sidewalls of gullies. By observing which direction the snow is blowing, and identifying features that encourage wind loading, are ways you can avoid this problem. Instabilities will be the greatest during peak storm intensity, or directly afterward. Snowfall may have stopped, but the wind can still transport it. Stay alert, watch for red flags, and choose terrain carefully.  

    Observe for cornices and blowing snow to point you in the direction of wind loading 

    Photo: Eric Falconer

Avalanche Discussion

An outing yesterday in the Old Ski Bowl, found above treeline terrain comprised of mostly wind effected snow. Some areas were softer than others. By mid-day below 9,000 feet, the top few centimeters of surface snow became damp, possibly from a green house effect. With overnight freezing temperatures, a crust may have formed. If so, this crust will be a good bed surface for new snow to slide on.  

Two factors to consider regarding the forecast: how much snow will fall and the wind direction when it arrives. On average, five inches of snow is expected near treeline, with a westerly wind. Weather models predict snow starting around 7am and lasting until 10pm at higher elevations. Snowfall rates may vary, and wind speed can change with direction. Stay attentive to the weather for the clearest picture.

If you get out, let us know what you're seeing by posting an observation on our website or through the Avy App.

Régions couvertes