Avalanche forecast

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Sawtooth Avalanche Center
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Avalanche danger

Mon
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Out of date — this forecast expired 8 months ago. You’re viewing past conditions, not the current bulletin.

Highlights

Your odds of triggering a slide increase as you climb in elevation and move to slopes that face away from the afternoon sun. Triggering a large avalanche is possible on steep slopes with soft, weak old snow buried beneath firmer recent snow. Digging into the snow below your boots or machine to look for this weaker layer, then choosing to ride simple terrain without it, is a great way to avoid avalanches today.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2.5

    You're most likely to trigger a large avalanche where dense slabs rest above weak, faceted snow and crusts. Observed avalanche activity during our recent storm focused on N-NE-E-SE facing slopes at middle and upper elevations. These areas harbor the weakest crust + facet combinations.

    Use your boots, hands, or poles to quickly check for "old snow"—crusts and/or weak, grey, sugary facets—beneath a slab of consolidated recent snow. Steep slopes with a slab-over-"old snow" setup are the most dangerous. Triggering an avalanche is possible in both wind-loaded and wind-sheltered terrain.

    Cracks shooting out from you and "whumpfing" sounds as the snowpack collapses are red flags that indicate unstable conditions. Avoid all steep slopes where you experience these obvious signs of instability. You may be able to trigger avalanches remotely—from gentler terrain above, below, or to the sides of steep slopes.

    (12/11/2025) These large avalanches released between 8,500-8,900' on NE and E aspects near Copper Mountain.

Avalanche Discussion

The danger dropped to moderate today, but triggering an avalanche is still possible and the consequences of taking a ride in a persistent slab avalanche are quite high. The recent large avalanches reported (from 12/6 to 12/10) broke multiple feet thick, and some broke widely, spanning multiple terrain features. Additionally, the snowpack is still thin, so taking a ride in a slide could involve being drug through downed trees, rocks, and other early season hazards.

Stability will gradually improve as the snowpack continues to adjust to the last storm's load, but this process can be slow and variable from slope to slope. Over the past few days, we've observed snowpack cracking, collapsing and unstable snowpack test scores. Obvious signs of instability like these make it an easy decision to stick to lower-angle terrain and slopes without obvious facets beneath the recent snow. Today, be on the lookout for these same clues and heed their warning by traveling conservatively.

You may also see a variety of small wet loose avalanches while out today. Use these as an indicator to move to colder, more shaded slopes as the sun and warm temperatures cook thin S, SW, and W facing slopes.

Regions covered