Avalanche forecast

Banner Summit

Sawtooth Avalanche Center
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Avalanche danger

Sun
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

    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.

     

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

Avalanche Discussion

Any thin surface crusts that formed overnight will break down quickly, following the path of the sun—E and SE in the morning and S, SW, and W in the afternoon. If you are traveling on a frozen snow surface, the likelihood of finding wet snow problems is low. However, once these crusts break down, the likelihood of human-triggered slides will increase greatly. Many slopes have shed over the last few days of warm temperatures, and signs of instability like rollerballs, pinwheels, and natural slides may not be obvious. A mushy, wet snow surface indicates that stability is deteriorating, and it is time to seek shadier slopes.

Plan your day to avoid traveling on or below steep slopes basking in direct sunlight, especially later in the day when temperatures and sunshine are at their peak. 

Cornices are large and may be unstable. On Tuesday, we easily triggered a 200' wide and up to 8' thick section of freshly formed cornice. 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. 

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