Avalanche forecast

Central Sierra Nevada

Sierra Avalanche Center
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Avalanche danger

Mon
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

Dangerous and active avalanche conditions are expected to continue today.  Strong winds with cohesive deposits of wind blown snow are expected to remain unstable today.  Intense April sunshine and warming temperatures will also create unstable wet snow avalanche conditions.  Conservative terrain choices are essential to avoid today's avalanche problems.  

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

    Continued strong to gale force SW winds overnight and into this morning will add to the existing wind slabs that have formed yesterday.  Natural and human triggered wind slab avalanches have occurred over the last 2 days and are expected to remain unstable today in near and above treeline areas.  Rapid warming and intense solar radiation could further weaken existing wind slabs causing avalanches to fail.

    Look for signs such as blowing snow, new cornice formation, wind pillows, and snow surface clues to where wind slabs have formed.  Avoid steep wind loaded terrain and areas below cornices.

    (4/16/2022)

    Wide wind slab avalanche propagation on Donner Peak, Donner Summit area. 

    Photo: Public

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

    Intense solar radiation and increasing temperatures will cause rapid warming conditions this morning.  As the snow surface becomes wet and deep, widespread roller balls and pinwheels along with larger wet loose avalanches are expected on all aspects and elevations.  With some areas in the forecast region receiving up to 3 feet of storm snow in the last week, these wet loose avalanches could be large in size and entrain a lot of this recent storm snow.

    As the snow surface becomes wet and deep it's time to move off of avalanche terrain or change aspects.  Roller balls and pinwheels will be signs that the snow surface is wet and losing strength, with larger wet loose avalanches becoming more likely.

Avalanche Discussion

  • Many NW-N-NE-E aspects have good snow coverage. Large areas of bare ground or very limited snow cover existed on most SE-S-SW-W aspects prior to snowfall this past week.
  • Snowfall this past week has greatly favored the Sierra Crest in the northern half of the forecast area. Substantial improvements in snow cover have occurred in this portion of the forecast area.

Regions covered