Avalanche forecast

West Mountains

Payette Avalanche Center
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Avalanche danger

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

Larger avalanches that fail on weak layers buried 1-2 feet deep are unlikely, but carry high consequences. You're most likely to find these persistent slabs on shaded, protected slopes facing east through northwest above 6,500 feet. Continue to use caution on very steep terrain-trap features, near cornices, and around other wind-affected slopes. Avalanches are unlikely in the low elevations.

Avalanche problems

  • Persistent Slabs

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

    Weak snow exists 1-2 feet below the snow surface. This layer is composed of surface hoar and near-surface facets from our prolonged high-pressure spell. Though becoming less likely, you are most likely to encounter this problem on shaded slopes facing NW-N-NE above 6,500 feet. Be heads-up around steep slopes that have been protected from the sun and wind, such as terrain features similar to those shown in the photo on the right. Persistent slab avalanches are becoming difficult to trigger. As more time has passed since the last major storm, it is unlikely that there will be any clear feedback (such as cracking, collapsing, or whumpfing) before an avalanche. The weight of a snowmachine is much more likely to affect buried weak layers than a person's weight.

    The most sensitive slopes are at mid-elevations. These could likely be small terrain traps that catch riders off guard, such as this one that claimed a life in early January in western Wyoming. Don't let your guard down when persistent slab avalanches are on the menu. Your best tools for managing this problem are safe travel practices, including traveling one at a time in avalanche terrain, keeping an eye on all members of your party, and digging into the snowpack to perform a snowpack test or check for weak snow at the depths mentioned. 

    ADDITIONAL DISCUSSION: Watch for small surface slabs of new snow, 2-4 inches deep at upper elevations, formed by gusty SW winds overnight. The problem above is the more consequential issue in this zone due to less snowfall. 

    (2/10/2026)

    Intentionally-triggered persistent slab avalanche. This failed on a layer of surface hoar two feet deep, which was buried 2/8.

    Photo: Payette Avalanche Center

Avalanche Discussion

Persistent slabs are the sleeping dragons of avalanche problems. The most challenging time for assessment as a rider can be right now, on the cusp of the transition from a drought, low-danger snowpack, back to a typical mid-winter snowpack that harbors weak snow in spotty locations. The dragons linger in a variable pattern across aspect and elevation, and while some are quietly going to sleep and may not awake for the rest of the season, others remain irritable. The tricky part is this: What is the likelihood that you poke the dragon and trigger an avalanche on a buried weak layer if you are in avalanche terrain? The answer is: unlikely, today. That likelihood increases if choosing terrain features where the few inches of snow that fell yesterday have stacked up deeper, or around/under the cornice features typical of ridgelines in this zone. Any moving surface snow has the potential to trigger a larger avalanche, even on slopes with existing tracks. Avalanche hazard is the likelihood of an avalanche impacting something of value, and for our purposes, that thing is you. Logically, as the likelihood of triggering an avalanche decreases, the avalanche danger also decreases. But while the likelihood of triggering a slide is decreasing, the consequences of getting caught remain the same. 

As you travel through the backcountry, recognize that you are almost always facing a low-probability but high-consequence scenario. The best way to manage this uncertainty is to build wide safety margins into your travel decisions. Be aware of the terrain you are traveling in, how you and your partners are traveling,  and picture the consequences of being caught in a slide in that terrain.

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