Bulletin d’avalanche

Mount Shasta

Mount Shasta Avalanche Center
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Danger d’avalanche

Wed
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
3 · Marqué
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Périmé — ce bulletin a expiré 8 months ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Avalanche hazard will rise drastically over the 24-hour forecast period. During daylight hours, triggering an avalanche large enough to bury a person will grow increasingly likely as snowfall accumulates. Choosing lower-angle, non-avalanche terrain during this time can help reduce one’s risk, however, abundant rocks and other obstacles are still present in the shallow snowpack. Overnight, the danger will increase to ‘HIGH’ as very heavy snowfall combined with extreme winds create very dangerous avalanche conditions at all elevations. Very large natural avalanches capable of running full path into low angle terrain are possible. 

Problèmes avalancheux

  • Storm Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Very Likely
    Taille
    2–4

    Human-triggered avalanches large enough to bury a person will become likely during daylight hours in both wind loaded and wind sheltered areas across all aspects. These slabs could fail on density changes in the new snow. A slight warming trend may also place weaker snow near the base of the storm snow. Wind drifting into leeward terrain may also create locally deeper and stiffer slabs. For anyone venturing into the backcounty, manage the problem by recreating on lower-angle, non-avalanche terrain without steep slopes above you. Red flags include failures on small test slopes, cracking, unstable snowpack test results and recent avalanches. Unfortunately, the shallow snowpack especially near and below treeline makes it difficult to safely enjoy the new snow without hazard from buried rocks and other obstacles.

    Overnight, the danger will increase significantly. Human triggered avalanches will become very likely as precipitation intensity peaks and extreme winds transport large quantities of snow. Very large avalanches capable or running full path are possible in the overnight hours and through the rest of the week. The Avalanche Center has issued a Special Avalanche Bulletin, which can be read above. Large avalanche run out zones on Mount Shasta, like Avalanche Gulch and the Old Ski Bowl, should be avoided until storm snow has time to settle. Both these areas are easily accessed from the Bunny Flat trailhead, where many holiday visitors will enjoy the snow. Know where you are going if traveling in the backcountry. The travel advice is simple beyond tonight: Avoid traveling in, near or below avalanche terrain.

Avalanche Discussion

Until terrain at the lower elevations begins to fill out, the snowpack especially near and below treeline harbors many hidden obstacles. Yesterday, only about a half a foot of snow existed at Bunny Flat and around a foot at 8,000 feet at the Shasta Alpine Hut.

Régions couvertes