Bollettino valanghe

Central Sierra Nevada

Sierra Avalanche Center
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Pericolo valanghe

Tue
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
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Non aggiornato — questo bollettino è scaduto 3 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Decent snow surface refreeze conditions occurred last night on open slopes. Once the superficial crust melts off sun exposed slopes, wet loose avalanches could be triggered by backcountry travelers navigating steep terrain. Terrain selection based on slope angles of less than 35 degrees is an easy way to avoid this avalanche problem if you so desire.

Problemi valanghivi

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    A decent but superficial snow surface refreeze is expected to have occurred last night, especially on open slopes. This followed several days of little to no overnight refreeze at the mid and upper elevations. Mountain valley floors where cold air pooled overnight will have the strongest refreeze. Higher up on the peaks air temperatures were in the upper 30s to mid 40s overnight, making snow surface refreeze fully reliant on radiational cooling of the snow surface under clear skies. As a result, there may be some areas under forest canopy away from valley floors where last night's refreeze is very weak. NW-N-NE aspect terrain steep enough for wet loose avalanches is expected to remain shaded and frozen all day today due to the still fairly low late January sun angle.

    Once the crust on the snow surface melts away across sun exposed E-SE-S-SW-W aspect terrain, expect wet loose instability to develop.  Remember that small wet loose avalanches can push you into rocks, trees, terrain traps, or over cliffs. Make terrain selections accordingly.

     

    (1/28/2024)

    Triggering pinwheels and small sluffs of loose wet snow are indications that a wet loose problem is present. SE aspect terrain, Silver Peak, Pole Creek area, CA

    Photo: Sierra Avalanche Center

Avalanche Discussion

The persistent slab avalanche problem that was with us for most of the season has been put to rest for now. Any lingering concern is specific to isolated areas along the eastern side of the forecast area where the snowpack is less than about 3 feet deep and still holds faceted, sugary snow in the lower half of the snowpack. This shallow and weak snowpack structure may not handle a large new snow loading event if one were to occur east of the Sierra Crest.

Regioni coperte