Bulletin d’avalanche

Central Sierra Nevada

Sierra Avalanche Center
Voir sur la carte

Danger d’avalanche

Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
1 · Faible
Open full map
Périmé — ce bulletin a expiré 9 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

MODERATE avalanche danger will continue to exist in near and above treeline terrain due to new wind slabs created by the strong NE winds and older wind slabs leftover from the recent storm. Human triggered avalanches remain possible. Identify where wind slabs exist and avoid steep wind-loaded terrain. Firm, scoured, or icy surfaces could also exist on exposed near and above treeline terrain.

Problèmes avalancheux

  • Wind Slabs

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

    E and NE winds have varied greatly by location since they started on Sunday night. In some areas, they have likely scoured previously wind-loaded N-NE-E aspects and redeposited the previous wind slabs onto the opposite aspects. Expect to find new wind slabs on W-SW-S aspects and on cross-loaded NW and SE aspects. These new wind slabs should remain limited to specific areas in near and above treeline terrain near ridgelines where the strongest NE winds have occurred. In areas where weaker NE winds occurred, some of the wind slabs that formed during the storm on the near and above treeline NW-N-NE-E-SE aspects may still linger. The possibility remains for the additional weight of a person on wind-loaded slopes to trigger new or old wind slabs today in some areas. 

    Use clues like blowing snow, cornices above slopes, drifted snow, ripples in the snow surface, and other wind created textures to identify where wind slabs may exist and avoid those areas. Travelling in sheltered non-wind-affected terrain should provide safer and more enjoyable conditions today. 

Avalanche Discussion

* Some continued skier triggered cracking on wind-loaded test slopes on Rubicon Peak.

* Widespread surface hoar on Rubicon Peak.

* Reports of E wind scouring in the Tamarack Peak area. Firm, icy, scoured surfaces may exist on any terrain exposed to the strong NE winds across the forecast area.

* Some evidence of reactive wind slabs on Donner Summit on Sunday in the form of skier triggered cracking and ECTP results.

Snow coverage is deepest in areas above 8000 ft. in the northern half of the forecast area (north of Emerald Bay). Even at these elevations, snow coverage varies by location. Some areas at the upper elevations south of Emerald Bay still have marginal snow coverage. Below 8000 ft. most areas still have patchy snow coverage with many exposed obstacles and areas of bare ground. 

Régions couvertes