Avalanche forecast

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Sawtooth Avalanche Center
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Avalanche danger

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

Anticipate wet snow avalanches in very steep, rocky terrain receiving direct sun. You could trigger a large avalanche where the wind has formed drifts and stiffened the snow surface. Cornices are large and may be unstable—give them a wide berth. 

Avalanche problems

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    Expect loose snow avalanches on very steep, rocky slopes receiving direct sun. These slides often initiate near the base of trees and rocks, gathering snow and growing in size as they move downhill. Rollerballs, or pinwheels, signify that the snow is heating up, and wet avalanches may soon follow. 

    While most will start small, they will be plenty large enough to knock you off your feet and carry you into unwanted terrain. Even small slides are consequential above terrain traps such as gullies, creeks, and thick timber. Plan your day to avoid lingering under steep, sunny slopes.

    Additional Discussion - Wind Slabs: Be on the lookout for 1-2' thick slabs near ridgelines and along steep mid-slope gullies. You can reduce your chances of triggering a wind slab by avoiding slopes with obvious signs of wind-loading, such as new cornice growth and large dunes or pillows of wind-blown snow. Cornices are large and may be unstable. Warming temperatures may cause overhanging cornices to sag and fail. Limit time beneath these features and give them a wide berth when traveling along ridges. 

    (2/20/2025) Several wet loose slides on the steep, craggy terrain near the Boundary parking lot. Photo: Sawtooth Avalanche Center

Avalanche Discussion

It's day 2 in a string of warm, sunny days. Last night, temperature inversions kept upper elevations warmer than lower elevations and will be ahead of the curve today as surfaces soften. Today's sunshine will have to overcome crusts at the surface, but upper elevation temperatures in the 40s F and strong sunshine will eventually turn the surface to mush. This wet snow may slide far and fast on crusts beneath the surface. The timing of wet snow avalanche problems varies greatly with location, aspect, and elevation and is nearly impossible to predict. Build this uncertainty into your travel plans and limit time on or under steep, sun-drenched slopes. 

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