Avalanche forecast

Central Sierra Nevada

Sierra Avalanche Center
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Avalanche danger

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

MODERATE avalanche danger will exist at all elevations today due to a combination of loose wet and wind slab avalanche problems. The vast majority of any avalanche activity that occurs today is expected to be human triggered, but an isolated natural avalanche is not impossible today or tonight.

Avalanche problems

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    Rapid warming under sunny skies and intense late March levels of incoming solar radiation will create widespread areas of snow surface melt today. Loose wet avalanche problems are expected to become increasingly widespread today and tomorrow. Expect the vast majority of instability to occur on steep E-SE-S-SW-W aspects. Loose wet avalanches are possible at all elevations today. Avalanche size up to D2 is possible (large enough to bury or injure a person).

    Identify and avoid steep slopes where natural or human triggered roller balls are occurring.

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    Lingering wind slabs left over from the past few days that formed under SW wind conditions will continue to present an avalanche problem in near treeline and above treeline areas today. Increasing NE winds today and tonight will redistribute snow on the ground creating new wind slabs. With this in mind, unstable wind slabs could exist on any aspect over the next 24 hours in near treeline and above treeline terrain. Avalanche size up to D2 is possible (large enough to bury or injure a person).

    Identify areas of concern by looking for signs of wind drifted snow both past and present. Recent wind slab avalanches, blowing snow, cornice formations, wind pillow deposits, snow surface texturing, and snow surface cracking can all be used to identify areas of potentially unstable wind slab. If in doubt, avoid avalanche terrain in areas where signs of potential wind slab instability are present.

Avalanche Discussion

* At least one and possibly two skier/snowboarder triggered wind slab avalanches occurred yesterday on E to SE aspect terrain near the top of Jakes Peak (West Shore Tahoe area). A report was received of a human triggered avalanche that was large enough to bury a person and a second report was received of a smaller wind slab avalanche that was most likely human triggered.

* Other observations from around the West Shore Tahoe, Pole Creek, and Donner Summit areas reported wind slabs near and above treeline with varying degrees of triggering sensitivity ranging from reactive to unreactive.

* Large cornices exist in numerous ridgetop areas and may present a hazard to backcountry travelers.

* No signs of instability were reported yesterday from below treeline terrain in the West Shore Tahoe, Pole Creek, and Donner Summit areas.

* Numerous crowns from deep slab avalanche activity occurring during the March 20 - 22 storm cycle exist on N-NE-E aspects both above and below treeline in the 7,000' to 10,000' elevation range. No reports of post storm deep slab avalanches have been received.

To the best of SAC's knowledge, triggering a deep slab avalanche has become very unlikely. For this reason it is no longer included as a specific avalanche problem. If you have unreported information relating to signs of deep slab instability occurring March 23 through the present, please submit an observation.

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