Avalanche forecast

Galena Summit & Eastern Mtns

Sawtooth Avalanche Center
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Avalanche danger

Sat
Alpine
4 · High
Treeline
4 · High
Below
3 · Considerable
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Out of date — this forecast expired 2 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Heavy snowfall and strong winds have created very dangerous avalanche conditions. Human-triggered avalanches large enough to bury people, snap trees, or destroy structures are very likely to occur. Slides can be triggered from long distances away from the slope that releases. Stay off and out from below steep slopes—slopes steeper than about 30 degrees. 

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    1–2

    Yesterday, Ben remotely triggered a large avalanche from a safe ridgeline in the Boulders. The avalanche was about 250' wide and released on weak snow near the ground (video at right/below). With continued snowfall today, 36-hr storm totals will reach 1-2' by nightfall. Strong to extreme S and SW built fresh, sensitive wind slabs in exposed terrain. Given the intensity of the wind, anticipate these slabs on any open slope, including the mouths of main drainages and roadways that typically funnel wind.

    While dangerous on their own, these fresh slabs are likely to release on the persistent weak layers described below. Cornices will be sensitive and may calve off to release slabs on the slopes below. Drifts, dunes, rippled snow surfaces, and chalky snow pillows are clues that the wind has been at work.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–3

    Expect to find dangerous slabs in areas affected by the wind. You could also encounter thin, sensitive slabs in areas sheltered from the wind as storm snow accumulates. These slides will break widely on a weak snow interface, including slick facets, crusts + facets, and surface hoar.  

    Triggering a very large, destructive 3+ foot thick avalanche on weak layers near the middle and base of the snowpack is likely. The odds that these deeper weak layers wake up will only increase as the storm intensifies again this evening and tomorrow. Observations indicate these avalanches are most likely as you move away from Galena Summit to this zone's shallower southern, eastern, and northern portions. 

    Anticipate touchy conditions that will only worsen as you climb into windier terrain. Persistent Slab avalanches can release in surprising ways. You can trigger them from flat or low-angle terrain long distances away from steep slopes, and they can break far above you. Snowpack cracking and collapsing are obvious clues that the slab + weak layer combination you've encountered is unstable. 

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