Avalanche forecast

Central Sierra Nevada

Sierra Avalanche Center
View on map

Avalanche danger

Sat
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
Open full map
Out of date — this forecast expired 4 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Areas of unstable snow and potentially dangerous avalanche conditions are expected to continue today in both wind exposed and wind protected avalanche terrain. Numerous easy to trigger avalanches occurred yesterday, some in sheltered locations well below the ridgetops. Cautious route finding and conservative terrain selection are essential today.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2

    Wind slab avalanches with 1 to 2 foot crowns and very wide propagation were easy to trigger yesterday in near treeline and above treeline terrain where wind drifted snow had deposited. Anticipate that some of this instability will continue today, especially on NW-N-NE-E-SE aspects.

    Identify and avoid areas of wind slab formation by using clues such as recent avalanches, cornices, and snow surface texture to highlight slopes of concern. Travel cautiously, giving slopes that hold wind slabs a wide berth. If the sun comes out today even just a little bit, rapid warming may make avalanches easier to trigger.

    (4/21/2022)

    Part of a 700' wide wind slab propagation in above treeline terrain, NE aspect. Andesite Peak, Donner Summit, CA

    Photo: Steve Reynaud

  • Storm Slabs

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

    Impressive storm slab avalanches with 1 to 1.5 foot crowns were easy to trigger yesterday in some wind protected areas well below ridgetops. Some of these avalanches in below treeline terrain connected together multiple avalanche paths with propagation up to 600 feet wide. Avalanches were failing about 4 inches above the old/new snow interface.

    Move cautiously today in wind protected terrain on all aspects. Make conservative terrain choices, especially in areas where recent avalanches, snow surface cracking, or unstable snowpit test results are present. If the sun comes out today even just a little bit, rapid warming may make lingering storm slabs easier to trigger.

Avalanche Discussion

  • Snow coverage has improved greatly since April 10th, especially along the Sierra Crest in the northern half of the forecast area. Many NW-N-NE-E aspects have good snow coverage. Snow cover on most SE-S-SW-W aspects is much thinner, mostly limited to the snow that has accumulated since April 10.

Regions covered