Boletín de aludes

Banner Summit

Sawtooth Avalanche Center
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Peligro de aludes

Sun
Alta montaña
2 · Moderado
Límite del bosque
2 · Moderado
Bajo el límite
1 · Débil
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Desactualizado: este boletín caducó 6 months ago. Estás viendo condiciones pasadas, no el boletín vigente.

Lo esencial

You are most likely to trigger a large avalanche on shadier middle and upper elevation slopes where the wind has stiffened the snow near the surface. Slides can be triggered remotely—from flat terrain below, above, and to the sides of steep slopes.

Problemas de aludes

  • Persistent Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible
    Tamaño
    1–2

    This problem is most concerning where wind-stiffened slabs formed atop weak snow surfaces (facets, crust + facet combos, and isolated surface hoar) that developed during a month-long drought. These weak layers are ugliest on shadier NW-N-NE-E aspects at middle and upper elevations.

    Thursday's remotely triggered avalanche in the White Cloud Mountains is a reminder that persistent slab avalanche problems are slow to heal. Snowpack cracking, collapsing, or whumpfing are clear signs of unstable conditions. However, a lack of these obvious warning signs doesn't mean you're in the clear.

    Persistent Slabs can release in surprising ways, break wider than expected, and be triggered from a distance. Your best way to play it safe today is by avoiding steep slopes facing the shady side of the compass where you suspect or feel that a slab has formed.

    Additional Discussion - Wind Slab: Be on the lookout for large dunes or drifts in upper elevation terrain. Given the variety of pre-existing slick surfaces and faceted snow, some of these recently formed wind slabs may remain sensitive to your weight. Although likely to be small, these slides can have outsized consequences in big terrain. 

    (2/10/2026) Slab avalanches near Elizabeth Lake in the Northern Sawtooths. NE @ 8,800'.

    Photo: Sawtooth Avalanche Center

Avalanche Discussion

New snow and wind earlier this week buried a variety of weak surfaces that formed in the January and early February dry spell. We’ve seen numerous avalanches failing on these buried weak layers. The common theme amongst the avalanches is 1.) They are most likely in wind-loaded terrain. 2.) 6-10" thick slabs are less likely but still possible to trigger in sheltered terrain if the new snow fell on the very weakest facets.

Wind Slabs: Thin wind slabs formed near the start of the most recent storms. These slabs are now covered by 6-10” of fresh snow. Using the typical visual clues might not work in spotting where they exist in the terrain. Try to feel with your hands or poles for a stiffer layer about 6-10” deep. If you find thin wind slabs overlying weak facets, you've found the equation to trigger a slide. To reduce your risk, consider moving to lower-angle slopes.

Soft Slabs on Facets: On slopes that lack a wind slab, triggering an avalanche is less likely, but not impossible. Where new snow fell on the weakest facets, triggering remains possible. 

Where are the weakest facets buried? Generally speaking, middle elevations that face NW-N-NE (worst on NE) have the weakest facets under 6-10” of snow. However, not every slope that fits this description has the right set-up to produce avalanches. You might go a whole day without getting an obvious sign of instability before you trigger a slide. All it may take is finding the weakest buried facets, and/or just a slightly stiffer slab. That might be as simple as a subtle aspect change, or just the right amount of slab stiffening via previous wind. Predicting these slides on a slope-by-slope basis is currently challenging. 

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