Bulletin d’avalanche

Mount Shasta

Mount Shasta Avalanche Center
Voir sur la carte

Danger d’avalanche

Wed
Alpin
4 · Fort
Limite forestière
3 · Marqué
Sous la limite
3 · Marqué
Open full map
Périmé — ce bulletin a expiré 3 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Very dangerous avalanche conditions exist. A large new snow load paired with strong southwest and westerly winds have installed fresh wind slabs on leeward slopes and sensitive storm slabs on all aspects and elevations. Identifying terrain traps and avoiding all wind-affected slopes and terrain steeper than 30 degrees, will be your best line of defense today.  

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Very Likely
    Taille
    1–2.5

    Winds will acquire more ammunition to build drifts as more snow falls and the day progresses. Watch for blowing snow and the development of wind lips and cornices to help determine wind direction. Assess representative slopes and feel for cohesive surface snow around wind-exposed terrain features. Dry snow of this nature will make snow transport easy and allow winds to carry snow over ridge tops, through trees, down gullies, and around the base of cliffs. Increasing surface textures near and below treeline, indicate the presence of wind activity.  

  • Storm Slabs

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

    Below and near treeline over a foot of new snow exists with more on the way. This extra load will only increase the risk and sensitivity of storm slabs as the day goes on. Trigger points are likely to be on or near steep convex terrain features such as gully walls, cliff tops, and mid-slope rollovers. Identifying and avoiding such areas will be the best terrain management tactic today. 

    (2/27/2023)

    Skier triggered storm slab a over a foot deep below treeline on convex terrain feature.

    Photo: E.Falconer

  • Loose Dry

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    1–1.5

    Given the amount of new snow and its dry quality, it is likely riders will be able to move dry-loose snow in terrain steeper than 30 degrees today. It's unlikely the dry snow will run fast or far but could catch a rider off guard and sweep them off their feet if unaware. 

    (2/27/2023)

    Dry-loose snow sluffing off rollover below treeline

    Photo: E.Falconer

Avalanche Discussion

Today is all about terrain choice. Near and above treeline, expect conditions to be windy, and cold with poor visibility. Maintain a healthy suspicion of aspects on the north half of the compass, specifically slopes that have seen more wind-deposited snow.  

Road/Recreation Status:

  • Everitt Memorial Highway is CLOSED. The gate is closed this morning. 
  • Castle Lake road is CLOSED

Régions couvertes