Avalanche forecast

Sawtooth & Western Smoky Mtns

Sawtooth Avalanche Center
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Avalanche danger

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

On slopes that face away from the sun, you're most likely to trigger a large avalanche failing on layers of weak sugary snow buried 2-3 feet deep. On slopes that face the sun, you could trigger loose snow avalanches once the upper snowpack becomes wet and mushy. Natural loose snow avalanches are possible during the heat of the day. 

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–2.5

    Dense 2-3' thick slabs overlie weak layers, including sugary facets, surface hoar, and crust + facet combinations on many NW-N-NE-E aspects. 

    Persistent slab problems can be tricky to deal with. Don't count on obvious signs of instability like snowpack cracking or collapsing to indicate an unstable slope. Your first sign of instability may be the avalanche you trigger. Persistent slabs may be triggered remotely—from above, below, and to the sides of steep slopes. 

    Simply avoiding avalanche terrain where these slabs + weak layers exist is the best way to stack the odds in your favor. 

    Additional Discussion: Whether a weak layer exists or not, the combination of recent snowfall and moderate winds formed slabs that may remain sensitive to your weight. Watch for dunes, waves, and textured surfaces created by wind.  Feel for stiff slabs overlying weaker or softer snow. These often form near exposed ridgelines. These smaller wind slabs, once moving, are an effective trigger for the larger Persistent Slab avalanches described above.

  • Loose Wet

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

    Wet  Loose avalanches are expected once the sun and warm temperatures turn the upper snowpack wet and mushy. Wet Loose avalanches are most likely to occur on steep slopes facing the sun (SE-S-SW-W). These avalanches could initiate naturally, especially on slopes under rocks or trees. They start at a point and entrain additional snow as they move downhill.

    Although beginning small, they can grow large enough to knock you off your feet or bury you in channeled terrain. Even small slides are consequential above terrain traps such as gullies, cliffs, and thick timber.

    Look for: Pinwheels, roller balls, or natural avalanches.Feel for: Moistening or wetting snow surfaces. 

    Seek shadier and/or lower-angle terrain once you begin to feel the upper snowpack turn into a consistency resembling oatmeal. 

Avalanche Discussion

Today's avalanche problems can be categorized into two buckets: Near-Surface and Deeply Buried. 

Near-Surface Problems: We're expecting to see Wet Loose avalanches once surface snow loses strength in the day's heat. These avalanches are expected to be small, but could push you into a bad place in more extreme terrain. Additionally, Wind Slabs are possible in exposed middle and upper elevations. Look for rippled, wind-textured snow surfaces. Feel for thicker, firmer slabs near ridgelines.  Both of these problems are at the surface and can be visually monitored and avoided by using terrain. 

Deeply Buried Problems: Across the advisory area, we have multiple buried weak layers in the upper 2-3 feet of the snowpack. Triggering a Persistent Slab avalanche on one of these layers is most likely on shaded, middle and upper-elevation slopes. The likelihood of triggering one decreases if you find a thick, supportable crust about 6-10 inches below the snow surface on lower and some middle elevation slopes. Obvious signs of instability, such as cracking or collapsing, have become less reliable indicators of these deeper instabilities.

Unlike the near-surface problems listed above, this problem cannot be managed with subtle terrain features. Entering steep, shaded terrain that lacks a stout crust 6-10 inches below the surface is rolling the dice. Unfortunately, the best way to reduce the odds of tangling with one of these avalanches is by continuing to avoid steep, shaded terrain.

Regions covered