Avalanche forecast

Central Sierra Nevada

Sierra Avalanche Center
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Avalanche danger

Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
Out of date — this forecast expired 7 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

LOW avalanche danger early this morning will increase to MODERATE avalanche danger at all elevations as the day progresses. A loose wet avalanche problem will develop in response to daytime warming.

Avalanche problems

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    Conditions were ideal last night for snow surface refreeze with air temperatures below freezing and clear skies for radiational cooling. As daytime warming occurs, snow surface melt will become sufficient for loose wet avalanches. The vast majority of loose wet avalanches today are expected to be human triggered and occur on E-SE-S-SW-W aspects. Loose wet avalanches will occur to a lesser extent on NW-N-NE aspects, mainly at low and mid elevations. Avalanche size is expected at D1 with size D2 possible in isolated areas.

    Timing and route options are key to managing this avalanche problem during backcountry travel in avalanche terrain. Steep sun exposed slopes will become increasingly unstable during the late morning through afternoon hours. Get into and out of sun exposed avalanche terrain early in the day. If you find yourself late for the ideal timing of travel, encountering surface wet snow with rollerballs and/or pinwheels, exercise route options that reduce avalanche hazard via low angle terrain choices.

Avalanche Discussion

* Three size D1 human triggered loose wet avalanches were reported yesterday from SE aspect, above treeline terrain on Mt. Rose proper.

* Unconsolidated recent storm snow, yet to be affected by melt lingers on steeper N aspects at the mid and upper elevations.

* Breakable to supportable melt-freeze crust exists on the snow surface in sun exposed areas, including on low angle northerly aspects.

* No wind slab avalanches were reported yesterday.

* The deeper snowpack remains well bonded with instabilities occurring relatively close to the snow surface.

Regions covered