Avalanche forecast

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Sawtooth Avalanche Center
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Avalanche danger

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

Generally stable conditions exist this morning.  The chance of triggering avalanches will increase today as the wind form drifts in exposed terrain. You can avoid windy areas to significantly reduce the chances of triggering an avalanche. 

Avalanche problems

  • Wind Slabs

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

    Today's snowfall and wind will probably create fresh wind slabs in exposed terrain. While sizeable avalanches are unlikely this morning, the slabs will grow and become more widespread this afternoon and evening, especially if thunderstorms develop and produce intense snow squalls and strong wind. 

    It's difficult to predict how well the fresh slabs will stick to the icy surfaces below them; the wind slabs could be difficult to trigger ("stubborn"), or they could release on their own ("naturally") or as soon as you touch them ("sensitive").  

    Watch for slabs near ridgelines and on the sides of cross-loaded gullies. This afternoon's possible convective activity could also produce graupel (round, styrofoam-like snow pellets), a potential weak layer for any slabs that form above it. Graupel tends to collect below large cliff faces, steep chutes, and couloirs, so there's a chance you could find sensitive slabs on relatively gentle pitches below steep slopes. 

    If the snow quickly becomes deeper and stiffer as you're moving, you've found a fresh slab. Cracks shooting out in front of your skis or machine are an obvious sign of unstable conditions. You can greatly reduce the chance of triggering an avalanche by avoiding windy terrain, especially in locations that receive at least 6" of snowfall.  

     

Avalanche Discussion

Today's weather adds a healthy dose of uncertainty to the avalanche equation. 

  • There is little hazard this morning. You might find isolated, small, thin wind slabs in alpine terrain, but large avalanches are unlikely. 
  • Light to moderate snowfall and moderate winds will gradually build wind slabs in exposed upper elevation terrain. This will be a straightforward, predictable process. 
  • Thunderstorms: Things will get more complicated—and a bit western—if significant thunderstorms develop. The storms can produce intense snowfall (2-5" per hour), strong winds (intense loading), and thick layers of graupel (a great weak layer where it collects and is buried on aprons below steep slopes). 

If you're out in an intense squall, expect slab and loose snow avalanches to release naturally in very steep terrain—pay attention to what is above you. While the slides should not be that large, they will quickly accelerate on icy surfaces and could be big enough to carry you where you don't want to go or bury people in terrain traps. The safe play is to dial back your terrain choices if strong storm cells materialize later today. 

Regions covered