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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Highlights

You could trigger wet snow avalanches on steep slopes basking in unobscured sun. You can reduce your risk by traveling on supportable snow and avoiding areas where you sink into a mushy, wet snowpack.

Avalanche problems

  • Loose Wet

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

    Two varieties of wet snow avalanches are possible on steep, wind-sheltered slopes once surface crusts turn mushy:

    1. Wet Loose:  These avalanches are most likely during the heat of the day on slopes that face the sun. They often initiate near the bases of trees, rocks, and cliffs. Although slow-moving, these avalanches are surprisingly powerful and difficult to escape. They may also trigger larger wet slab avalanches (example) as they move downhill.
    2. Wet Slab: These large avalanches are unpredictable. They release as buried weak layers become wet. We anticipate these avalanches to break 1-4 feet thick, creating a dangerous, likely unsurvivable avalanche. They can break widely and without warning. The only way to reduce your risk is to avoid traveling on or under steep slopes. 

    Additional Discussion - Cornices: Avoid large, overhanging cornices. The heat will cause these to sag and break. Scary in their own right, they also serve as excellent triggers for the two wet avalanche concerns described above. 

    Large Wet Loose avalanche in the Northern Sawtooths near Williams Peak. NE 9000'.

    Photo: Sawtooth Avalanche Center

Avalanche Discussion

Below-freezing temperatures overnight have frozen the snow surface. Once surface crusts break down, be wary of entering very steep slopes. Many of the easy-picking slopes have avalanched naturally over the last week of warm temperatures, and natural avalanches are unlikely—the more pressing concern would be triggering one of these slides in very steep terrain where you could be knocked off your feet and carried where you don't want to go.  

Last night's freeze and cooler temperatures today will slow the meltwater making its way deeper into the snowpack. However, one night of below-freezing temperatures won't be enough to completely halt water movement. Wet slabs are unpredictable and can occur days after a warm-up, leaving us with some unknowns. We haven't seen widespread evidence of wet slab avalanches, but that doesn't mean we are out of the woods yet, and natural or human-triggered avalanches aren't totally out of the question.

To reduce your risk of triggering a large wet snow avalanche, plan to start and end your day early before the upper snowpack becomes wet and unsupportable. 

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