Avalanche forecast

Banner Summit

Sawtooth Avalanche Center
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Avalanche danger

Fri
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Highlights

Large natural and human-triggered wet avalanches are likely today on slopes where the sun and warm temperatures are rapidly destabilizing the snowpack. On slopes holding colder snow, triggering a large slab avalanche is still possible, especially in wind-affected terrain. Be prepared to start and end your day early, and don't linger beneath large, rocky avalanche paths facing the southern half of the compass.

Avalanche problems

  • Wet Slabs

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

    Two varieties of wet snow avalanches are likely on steep, wind-sheltered slopes. Large Wet Slab avalanches may release naturally as buried persistent weak layers become wet. Smaller Wet Loose snow avalanches are very likely to be triggered and could entrain large amounts of snow as they move downhill.

    1. Wet Slab avalanches are unpredictable, can break widely, and occur without obvious warning signs. These avalanches are expected to break 1-4 ft deep on lubricated buried crusts or wetted weaker snow layers underneath slabs formed in February and March.
    2. Wet Loose avalanches are more predictable and typically start as small point releases before entraining snow and fanning out below. These slides often initiate near the base of trees, rocks, and cliffs, and primarily will involve only the recent snow. These slides can trigger larger slab avalanches (example) as they move downhill.

    Rollerballs (video), pinwheels, and wet, slushy snow surfaces are clear signs the snow is heating up and that wet avalanches may follow. Even small wet slides are surprisingly difficult to escape and are consequential above terrain traps such as gullies, creeks, and trees. Minimize your time spent under steep, sunny slopes, especially those with rock and cliff features that warm quickly, and particularly later in the day.

    Additional Discussion - Cornices: Cornices could break on their own as they sag during the multi-day heat spell. Natural cornice fall can trigger both wet loose slides and larger slab avalanches.

    (3/16/2026) This natural wet loose avalanche released mid-day on Monday, March 16th at middle elevations in the Meadow Ck drainage near Williams Peak, Sawtooth Mtns. Note how it "tried" to flank out as a slab avalanche as it moved downslope. 

    Photo: Friends of the SAC Governing Board

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1.5–2

    It is possible to trigger large slabs in wind-loaded terrain where the snowpack remains cold.

    • Recent winds built wind slabs below corniced and exposed ridgelines, on the sides of cross-loaded gullies, and in cirques below steep faces, large cliff bands, and chutes. These are most common at upper elevations but also exist in middle elevations and may be found lower on slopes than expected.
    • Look for smooth snow pillows, dunes, textured snow surfaces, and cornices. Feel for stiff snow and listen for hollow or "drummy" sounds.
    • Wind slabs are fairly easy to identify and avoid. Snowpack cracking and collapsing are clear signs of unstable conditions. Give cornices a wide berth; they can break on their own or with the weight of you or your sled.
    • These avalanches may break more deeply or widely than expected, as the slab may be resting on buried weak layers (sugary facets, surface hoar, and crust + facet combinations). Be extra cautious if choosing to enter avalanche terrain on NW, N, NE, and E facing slopes, where the Persistent Slab problem is at its worst.

    (3/15/2026) Natural avalanche in wind-loaded terrain near Cape Horn Summit. 

Avalanche Discussion

Scott called conditions funky in the forecast a couple of days ago, and that is pretty out of character for him. We’re right on the edge of a big shift for the snowpack, and funky things happen around that tipping point. As water is introduced to the snowpack, it weakens interfaces between slabs and lingering persistent weak layers or crusts, causing avalanches. These large water-induced avalanches, Wet Slabs, are a whole lot harder to pinpoint the timing of than dry slab problems. This challenge is due to the spatial variability of heating, and therefore water production, across the forecast region, throughout a drainage, and even across individual slopes.

We’re diving into our third day of record-breaking temperatures with very little overnight cooling, and we suspect that water is about to start tickling those buried weaker interfaces, resulting in funky large natural avalanches. A winter snowpack never likes to go down without a fight, and the next couple of days may just be that fight. Avoid travelling on or under avalanche terrain where the surface is becoming unsupportable and punchy to keep out of trouble.

If your plan is to try to dodge big honkin' wet slabs, you may still encounter wind slabs and persistent slabs on slopes holding cold snow.

Regions covered