Avalanche forecast

Banner Summit

Sawtooth Avalanche Center
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Avalanche danger

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

Wet snow avalanches are likely in steep, rocky terrain receiving direct sun—be wary of traveling on or below these slopes, especially later in the day.  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

    Loose snow avalanches are possible on very steep, rocky slopes receiving direct sun. Avalanche activity is most likely on S-facing slopes by midday and on W-facing terrain this afternoon. 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. A mushy, wet snow surface indicates that stability is deteriorating and the likelihood of triggering a slide is increasing. 

    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.

     

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

Avalanche Discussion

Without a solid freeze overnight, the upper snowpack has remained wet, and any thin surface crusts formed overnight will quickly break down on slopes basking in unobscured sunlight. Today's wet snow problems will follow the sun's path—E and SE in the morning and S, SW, and W in the afternoon. Many slopes have already shed and slid naturally over the past few days of strong sun and warm temperatures, so widespread naturals or signs of instability, like rollerballs or pinwheels, may not be obvious. If you encounter a wet, mushy snow surface, you could trigger a wet loose slide, particularly on very steep, sun-drenched slopes. To manage this, avoid lingering under or traveling on steep slopes during the heat of the day or where the upper 5–8 inches of the snowpack is wet and mushy.

Be wary of traveling near or under hanging cornices. Warm temperatures may cause these overhanging cornices to sag and fail. Yesterday, near Copper Mtn. We found many large, sagging cornices along ridgetops, many of which have already failed. 

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