Bollettino valanghe

Central Sierra Nevada

Sierra Avalanche Center
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Pericolo valanghe

Alta quota
1 · Debole
Limite del bosco
1 · Debole
Sotto il limite
1 · Debole
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Non aggiornato — questo bollettino è scaduto 8 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

LOW avalanche danger continues for all elevations. Avalanche activity remains unlikely, but keep an eye out for isolated instability in any areas where drifting snow accumulates.

Problemi valanghivi

  • Cornices

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely
    Dimensione
    1

    S to SW ridgetop winds are going to blow hard today, gusting up to 115 mph. This will certainly scour and transport any snow that remains available for wind transport. The big issue is that previous SW wind scouring and melt-freeze crust formation on windward aspects has left very little snow available for wind transport. In the unlikely event that new areas of unstable snow can form today, characteristics will be that of a wind slab. Avalanche size is expected to be too small to bury a person (size D1).

    Move around the mountains today exercising normal caution. Have a travel plan for the day, travel through avalanche terrain one at a time, regroup out of avalanche terrain, and practice effective communication within your group. Keep an eye out for any isolated areas where drifting snow is accumulating and the unlikely encounter with a newly formed, unstable wind slab.

Avalanche Discussion

* Observations made yesterday on Talking Mountain (Echo Summit area), Silver Peak (Pole Creek area), and Johnson Canyon (Donner Summit area) all matched well with previous observations from around the forecast area and gave no indications of snowpack instability. Thin snowcover and early season conditions exist in many areas.

* The upper layers of the snowpack on NW-N-NE-ENE aspects continue to hold a mix of near surface facets, varying degrees of the Dec 4 buried surface hoar layer, areas of old wind slab, and wind scoured snow surfaces depending on exposure to or protection from SW and NE winds.

* Surface melt-freeze crust has formed in most areas on E-SE-S-SW-W aspects.

* The mid and lower protions of the snowpack on all aspects are well bonded and lack a problematic weak layer.

Regioni coperte