Bollettino valanghe

Central Sierra Nevada

Sierra Avalanche Center
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Pericolo valanghe

Wed
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
Non aggiornato — questo bollettino è scaduto 4 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Unstable wind-drifted snow may still exist on open slopes near ridges. Additionally, wet snow could slide downhill on sunny slopes as the day warms up. Traveling in wind-sheltered areas on cool shady slopes could help reduce exposure to these avalanche problems. 

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    During the last few days, strong NE winds have deposited slabs of wind-blown snow on NW-W-SW-S-SE aspects near ridgelines. A few wind slabs may still linger on N-NE-E aspects that escaped scouring or in complex terrain where the NE winds cross-load these slopes. Wind slab avalanches could still be possible today on steep wind-loaded slopes in near and above treeline terrain. While some wind slabs could be small and not involve much snow, some wind slabs could be large enough to bury or injure a person.  

    Blowing snow, cornices above a slope, wind drifts, wind-created surface textures, and snow surface cracking can all help identify where fragile wind slabs may exist. Move around these areas with caution. Places sheltered from the winds will hold more consistent and less wind-affected snow. 

    (3/7/2022)

    Small wind slab and cornice collapse on a NE aspect with NE wind protection along the Deep Creek Ridge.

    Photo: Andy Anderson

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    Widespread wet snow could exist today due to warmer weather at all elevations, decreasing NE winds, and strong March sunshine. Sheltered gullies and areas near sunny rocks or trees will warm up the fastest, but wet snow should form on most sunny E-SE-S-SW-W aspects as the day warms up. A few wind-exposed slopes at upper elevations may avoid significant warming if the NE winds stay strong enough to keep the snow cool. Wet loose avalanches will be possible today. Wet loose avalanches gather more snow as they move downhill, so long steep slopes can produce larger wet loose avalanches. 

    Look for signs of wet snow as you travel. When you start to see rollerballs, pinwheels, or other signs of wet snow, it is time to avoid steep slopes and move into lower-angle terrain.

    (3/6/2022)

    Skier triggered D1 wet loose avalanche on a SE facing gully on Mt. Houghton above 9000 ft. 

Avalanche Discussion

  • A skier-triggered wet loose avalanche occurred on March 6 in a SE-facing gully on Mt Houghton where the sun was strong enough to create wet snow despite air temperatures remaining below freezing. 
  • Several small wind slab failures have been reported around the forecast area since Saturday (Blue Lakes, Silver Peak, Tamarack Peak, Deep Creek Ridge, Talking Mountain).
  • Strong NE winds have left firm scoured surfaces on many of the exposed N-NE-E aspects at upper elevations.  
  • Snowmelt on SE-S-SW aspects has exposed bare ground in many areas, limiting over snow travel options on these aspects.
  • The old near surface facet layer that was buried on Feb 14 following the prolonged Jan/Feb dry spell continues to gain strength. Any areas where this layer remains drier and weaker with the ability to collapse and propagate will be extremely isolated across the forecast area if they exist at all.

Regioni coperte