Avalanche forecast

Eastside Region

Eastern Sierra Avalanche Center
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Avalanche danger

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

Triggering large avalanches is likely in terrain where the wind has deposited snow. These are most likely near and adjacent to ridgelines. 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
    Likely
    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. Wind-deposited snow is our main concern for triggering a large avalanche today. They'll be largest and most sensitive as you get closer to ridgelines, however it is still possible to trigger them 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 drifts, dunes, and pillows. 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 and adjacent to ridgelines, where you should give cornices a large berth. They can be triggered from the edges where they're thinnest and can break farther than expected. Small loose snow sluffs are possible in steep terrain, potentially running fast and far on slick crusts. As the sun comes out and temperatures rise today, keep in mind that the surface of the snow can moisten, causing wet instabilities in the new snow as well. 

    (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: 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 day, with the storm snow primarily falling right-side up.

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 and ajacent to ridgelines, increasing in size as you climb up in elevation. You will still be able to find larger slabs in isolated locations a mid-elevations on the leeward side of catchments like gatherings of trees. Due to limited visibiltiy during the storm yesterday in whiteout conditions, we're left with some uncertainty in how this new snow is bonding to old surfaces until we're able to get good visibilty during the day today. Terrain selection is the best way to manage uncertainty by limiting your exposure to avalanches. 

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