Avalanche forecast

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Sawtooth Avalanche Center
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Avalanche danger

Mon
Alpine
4 · High
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

Conditions will become downright scary today. Large natural and human triggered avalanches are near certain to release in windy terrain. The chance of avalanches in more sheltered areas will increase as the storm progresses.  

The danger will peak tonight - plan to be out of the mountains before dark. 

Avalanche problems

  • Wind Slabs

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

    Expect to trigger 1-4 foot thick slabs in wind-loaded terrain. Some avalanches will release naturallly, and cornices could fail and trigger slabs on the slopes below.  Avalanches could be wider than you expect, and very easy to trigger, due to persistent weak layers (facets and crust + facet combinations) buried below the slabs on many slopes that face the northern half of the compass. You could remotely trigger an avalanche from lower-angled terrain above, below, or to the side of a steep slope.

    Expect to find slabs near and below ridgelines, on the sides of cross-loaded gullies, and on aprons beneath chutes. The wind slabs will be most widespread at upper elevations but may exist in middle elevation terrain. 

    Wind-drifted snow will feel stiff and may keep you on the surface. Watch for dunes, drifts, and snow pillows. Cracks shooting out from your skis or boards are a clear sign you've found a wind slab. 

    The size and chance of avalanches will increase as the day progresses. The slope you safely played on in the morning may not be safe later today. The prudent move is to steer clear of large, wind-exposed avalanche paths, including the runouts where avalanche debris would end up. 

    (3/13/2025) Remotely triggered slab avalanche on Paymaster Peak at 9200' NW aspect. This was triggered from ~100' feet away on a ridgeline.

    Photo: Sawtooth Avalanche Center

  • Storm Slabs

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

    In areas more sheltered from the wind, the chance of slab and loose snow avalanches will increase as the storm progresses. These avalanches are most likely on slopes steeper than about 35 degrees.

    The storm snow sits atop facets,  facet + crust combinations, and crusts, depending on aspect and elevation. Slabs and sluffs will be easier to trigger in some areas than others, and the differences in stability between aspects may not be easy to recognize. 

    A kiss of wind, mild temperatures, or a little drizzle or rain is all it takes to consolidate the storm snow into a touchy slab. Although smaller than the thicker wind slabs described above, this problem could be tricky to manage. Slabs may release in surprising ways and break wider than expected. They may be triggered from a distance—above, below, or to the sides of steep slopes. It will be hard to predict which slopes are becoming unstable as the storm progresses, so build a wide safety margin to handle the uncertainty. 

    Expect heavy sluffing on many steep slopes. Triggered slides of any form may quickly gain mass and speed as they move downslope on hard crusts. 

Avalanche Discussion

Rain is likely at lower elevations today and tonight, and we could see a natural cycle of small avalanches involving the recent storm snow. Avoid walking or hanging out directly beneath steep slopes if steady rain is falling. 

In recent days, we've seen and received reports of some remotely triggered avalanches and long running cracks and collapses, signs the recently buried facets and crust + facet combinations are not quickly adjusting to the new load above them. This storm may cause the weak snow beneath to misbehave, or it could be a short-lived instability; the safe move is to treat the recent observations as foreshadowing until proven otherwise. Assume that conditions will be touchy (easy to trigger avalanches on steep slopes), and be pleasantly surprised if stability is better than expected.  

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