Avalanche forecast

Central Sierra Nevada

Sierra Avalanche Center
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Avalanche danger

Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

MODERATE avalanche danger exists at all elevations today due to lingering wind slabs and possibly some remaining storm slabs. Human triggered avalanches will remain possible today. If any doubts exist about the stability of a slope, avoid it and move on to something lower angle with less uncertainty.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    Human triggered wind slab avalanches will remain possible today. Unstable wind slabs could still linger on wind-loaded N-NE-E aspects and cross-loaded NW and SE aspects in near and above treeline terrain. Avalanches resulting from these wind slabs could involve enough snow to bury a person (size D2). Smaller isolated wind slabs in below treeline terrain may still remain possible as well. 

    Use clues like cornices above slopes, wind pillows/drifts, ripples on the snow surface, and other signs of wind-loading to identify and then avoid places where wind slabs may exist. Some of these slabs could still be triggered from a distance. Plenty of great snow and recreation opportunities exist on lower angle more sheltered slopes.

  • Loose Dry

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    Some unstable storm slabs may still lurk in near and below treeline terrain especially in areas where a thin weak layer of surface hoar may exist below the new snow. A high degree of uncertainty exists as to where these storm slabs may linger and whether or not they remain unstable. If any storm slab avalanches occur, most of them would remain small, but some could still involve enough snow to bury or injure a person especially in areas around terrain traps. 

    Recent avalanches, shooting cracks or collapses, or unstable snowpit tests can all help identify where unstable storm slabs may still exist. Actively look for signs of instability and avoid areas with potential problems. If in doubt assume a slope could remain unstable and avoid it. Due to the high degree uncertainty associated with this problem more conservative decision making would be a prudent choice for today.

Avalanche Discussion

* Observations on Andesite Peak showed widespread natural wind slab avalanches yesterday as well as a skier triggered wind slab that was triggered remotely. Another skier triggered wind slab avalanche occurred on Rubicon Peak. The crowns for these avalanches ranged from 8 to 12 inches in depth. For more information click on the observations below.

* Numerous signs of instability including test slope failures, shooting cracks, and unstable snowpit test results were reported in the Castle Peak, Andesite Peak, Tamarack Peak, and Rubicon Peak areas in wind-loaded and non-wind-loaded terrain at all elevations.

* Widespread wind-loading occurred throughout the day across the forecast area along with continued snowfall. 

* Snow coverage has improved greatly in most places, but there are still many obstacles on or near the snow surface in some areas. 

Regions covered