Avalanche forecast

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Sawtooth Avalanche Center
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Avalanche danger

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

You're most likely to trigger a large avalanche on steep slopes facing the northern two-thirds of the compass. You may be able to trigger avalanches remotely—from flat terrain below, above, and to the sides of steep slopes. Watch for and avoid fresh, stiff wind drifts.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–2.5

    Slabs that formed in early February rest above a variety of ugly, widespread, weak layers (facets, surface hoar, crusts, and combinations). The snowpack is gradually stabilizing, but the steady stream of snowfall is maintaining the chance of triggering slides. You are most likely to trigger a dense, 2-4 foot thick avalanche where:

    • Any part of the slope you are on or connected to is steeper than about 35 degrees
    • The slope faces the northern 2/3 of the compass
    • The slab is less than about 3' thick—relatively shallower spots may exist where the wind frequently blows, and the slab is not uniformly thick.

    Before triggering an avalanche, you may or may not experience obvious signs of instability like snowpack cracking and collapsing or whumpfing. Persistent Slabs can release in surprising ways, break wider than expected, and release above or hundreds of feet away from where they are triggered. We can't assume tracks on a slope mean it is safe; several people could descend a slope before triggering an avalanche.

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    Isolated wind slabs up to 2 feet thick formed in recent days. The slabs could rest above weak crust and facet combinations on southerly aspects or small sugary facets on more north-facing slopes, making the slabs easier to trigger than you might expect. You're most likely to find the slabs immediately beneath exposed upper elevation ridgelines and on the sides of cross loaded gullies. Today and tonight's expected snowfall and wind could increase the size and chance of triggering existing slabs. 

    Loose snow avalanches: If you're playing in very steep, shady terrain, expect to trigger sluffs involving  today's snowfall and the 8-12" of snow that has fallen over the past few days. 

    (2/15/2025) This natural wind slab avalanche released naturally on Feb 14 or 15 in the Goat Ck drainage. SE aspect near 10,000'. The slide may have been triggered by cornice fall. It appeared to involve the snow that fell on Feb 13-14. 

    Photo: Sawtooth Avalanche Center

Avalanche Discussion

Yesterday's clear skies revealed a fresh, natural slab avalanche that released on a wind-loaded SE aspect near 10,000' in the Goat Ck drainage between Ketchum and Galena Summit (photo and details). This avalanche appeared to involve the snow from the Feb 13-14 Valentine's Day storm. It may have released on a crust+facet combination that formed during the arctic cold snap last week. This slide could be an outlier, or it could be foreshadowing, introducing another persistent weak layer.

Also, another round of thin crusts formed on some steep, sunny slopes over the past couple days and is now getting buried. With continued snowfall and possible wind-transported snow in the forecast, the prudent move is to treat freshly wind-loaded or drifted avalanche starting zones with caution.   

Regions covered