Avalanche forecast

Central Sierra Nevada

Sierra Avalanche Center
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Avalanche danger

Wed
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Avalanches will be possible today where wind-blown snow fills in terrain features, especially on the downwind side of ridges, in gullies, or on other wind-exposed places. Move around these areas with caution, especially if you see signs of active blowing snow or unstable snow, such as cracking or recent avalanches. 

Avalanche problems

  • Wind Slabs

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

    Use clues like blowing snow, ripples on the snow surface, and other wind-created surface textures to help identify where wind slabs might exist.  If you move into an area where the snow feels denser or deeper than other places nearby, you may also be in a wind-loaded spot. Cracking in the snow or recent avalanches are sure signs that unstable snow exists. Recognizing where the wind slabs exist and choosing to avoid those areas can help reduce your exposure to this avalanche problem. 

    As new snow falls today, the strong SW winds will blow it into terrain features on the downwind sides of ridges, in gullies, or in other places where wind-blown snow accumulates. The wind-blown snow will fill these areas with deeper, denser deposits and form wind slabs. Expect these wind slabs to form quickly today as new snow and wind impact the forecast area. The largest wind slabs will form in the areas where the most new snow falls. In areas where less new snow accumulates, the wind slabs will remain smaller. These wind slabs will likely form faster than they can bond to the underlying snow surfaces, and human-triggered wind slabs may become possible today. 

Avalanche Discussion

Repeated melt-freeze cycles and previous rain events have transformed the snowpack into late-spring or even summer-like snow with well-established drainage. In areas that get rain on snow today, the snow surface may get wet, but the established drainage should allow rain to quickly drain through the snowpack and help limit the chances of wet loose avalanches. 

March's record-setting heat and strong sun have caused dramatic snowmelt on all aspects and elevations, especially below 8000'. Large areas of bare ground and open, flowing creeks with few to no snow bridges are making the approaches to terrain difficult in many places. Northerly aspects offer better snow coverage, but obstacles like rocks, stumps, and logs have melted out on these slopes as well. Today's new snow may hide some of these exposed obstacles.

Regions covered