Avalanche forecast

Eastside Region

Eastern Sierra Avalanche Center
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Avalanche danger

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

It is possible to trigger an avalanche in terrain where the wind has deposited snow. These are most likely near ridgelines and on the leeward side of mid-slope features like gullies, rollovers, and couloirs. Drifts, dunes, and wind-sculpted snow surfaces are signs the wind has been at work. Cracks shooting out from your skis or board are a sign you've found an unstable slab. 

Avalanche problems

  • Wind Slabs

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

    A winter storm brought extreme winds out of the S-SW-W yesterday, with around 10 inches of new snow falling in our most favored locations on Saturday. Wind-deposited snow is our main concern for triggering an avalanche today. They'll be largest and most sensitive just below ridgelines, on wind-exposed near-treeline slopes. These new slabs sit on top of a variety of weak surfaces, including crusts and facets. 

    Be on the lookout for blowing snow, drifts, and dunes. Stiff wind-textured snow surfaces that sound hollow, like a drum or styrofoam, are a sign the wind has been at work. Cracks shooting out from the bases of your skis or board are a sign you've found an unstable slab. These are most likely near ridgelines and on the leeward side of mid-slope features like gullies, chutes, and couloirs. Be sure to give cornices a large berth. 

    (12/12/2024) Photo: Eastern Sierra Avalanche Center

Avalanche Discussion

A short but intense storm brought up to 11 inches of snow to the most favored location in our forecast area on Saturday: Tioga Pass. The Mammoth Crest picked up 8 inches of snow, with the southern and most northern parts of our forecast area only receiving 3 to 7 inches. While the storm underperformed for precipitation, the winds did not. Sustained strong to extreme S-SW-W winds blew snow throughout the day, causing near whiteout conditions from the alpine down to the 395 from Crowley north. Temperatures stayed cool throughout the storm, with the new snow primarily falling right-side up. While we got a break in the weather yesterday, strong winds picked back up overnight and continued to blow snow. While some snow may fall this afternoon, wind transport is the main input for instability.

These wind-deposited slabs were laid on top of a variety of weak surfaces. On northerly slopes, these firm wind-plastered slabs lay on top of soft facets. On more solar or lower elevation slopes, expect to find them on top of a variety of crust/facet combinations. Heading into the mountians today, these will be most sensitive to triggering near ridgelines and in mid-elevation catchment zones such as mid-slope rollovers, the sidewalls of gullies, or gatherings of trees. We're left with some uncertainty in how this new snow is bonding to old surfaces across our forecast area. Terrain selection is the best way to manage uncertainty by limiting your exposure to avalanches. 

Regions covered