Avalanche forecast

Central Sierra Nevada

Sierra Avalanche Center
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Avalanche danger

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

Avalanches remain possible today where slabs of wind-blown snow rest on top of old, weak snow on open slopes, near ridges, or in gullies. In some places, enough warming may occur for sluffs of wet snow. Watch for any signs of unstable snow, like recent avalanches, cracking, or wet snow. You can reduce your chance of triggering an avalanche by using less steep slopes and sticking to areas without wind-blown snow.

Avalanche problems

  • Wind Slabs

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

    Triggering a wind slab avalanche remains possible today where wind-blown snow has piled up on a fragile layer of buried surface hoar. These lingering wind slabs will exist in areas where winds were strong enough to move snow but weak enough to let the surface hoar persist. This combination will most likely exist in near treeline, NW-N-NE facing terrain. While most wind slabs should remain small since very little new snow fell, some may be large enough to cause problems for people since the surface hoar could allow them to break wider than expected. 

    Cornices or wind lips above a slope, wind drifts, ripples in the snow surface, and other wind-created textures can help identify where wind slabs exist. Recent avalanches or cracking in the snow indicate that the wind slabs remain unstable. These wind slabs could fail lower on a slope than typical wind slabs since the surface hoar may not exist at the top of the slope. This possibility of triggering an avalanche part way down a slope will make determining which slopes could be problematic more difficult. Traveling in sheltered areas where wind-blown snow has not piled up can reduce the chances of triggering a wind slab avalanche and may help find more consistent snow. 

     

    (2/27/2024)

    Surface hoar buried under 20 cm of wind slab. N aspect terrain near Ophir Peak, NV.

    Photo: Sierra Avalanche Center

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    Sunny skies and warmer weather today could allow some wet snow to form on sunny slopes, especially in mid to lower-elevation areas. The increased winds at the upper elevations should help limit the amount of wet snow that forms. Most wet snow instabilities should present as pinwheels and roller balls, but some larger sluffs of wet, loose snow may become possible on slopes that experience the most warming.

    Watch and feel for changes in the snow. When it starts to feel wet or you see signs of unstable wet snow like roller balls or pinwheels, consider changing aspects or moving to lower-angle slopes.

Avalanche Discussion

Recent observations have shown that surface hoar remains on NW-N-NE aspects in near and below treeline terrain. In some places, wind slabs, like those mentioned in the wind slab problem above, rest on top of it. In more sheltered areas, a thin layer of snow rests on top of it, and in some places it remains on the surface. This layer will likely fail and produce avalanche activity during the upcoming storm.

Regions covered