Avalanche forecast

Sawtooth & Western Smoky Mtns

Sawtooth Avalanche Center
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Avalanche danger

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

You are most likely to trigger avalanches where the wind has formed drifts or stiffened the snow surface. The fresh slabs are largest and most widespread in upper elevation terrain and in bowls below steep cliff bands.

Avalanche problems

  • Wind Slabs

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

    Recent northerly winds have formed both soft and stiff slabs. Some of these slabs overlie weak facets or crusts—especially on SE-S-SW aspects—and may be more sensitive to triggering than you might expect. Yesterday near McDonald Pk, I observed a wind slab that stepped down to one of these deeper weak layers (photo above/right). 

    Wind slabs will be thicker, wider, and more common at upper elevations. Look for wind-blown snow immediately below exposed ridgelines, on the sides of gullies or chutes, and near large terrain features. You could also find slabs below large cliff bands and on the aprons of chutes and couloirs.  

    Cracks shooting out from your skis or sled are an obvious sign of instability. Watch for drifts, dunes, and ripples on the snow surface. Wind slabs can have a smooth, chalky appearance and feel and sound hollow, like a drum. Wind-deposited snow will be stiffer and keep your skis or snowmobile on or closer to the surface. Managing this problem is relatively simple. Steer clear of recent wind drifts and slabs on slopes steeper than about 35 degrees. 

    (2/15/2023) This wind slab avalanche released on a SE aspect at 9,500' near McDonald Peak in the southern Sawtooths.

    The slide "stepped down" to break into a deeper weak layer before coming to rest on a bench.

Avalanche Discussion

Steering clear of recently formed drifts and slabs is the most effective way to stay out of trouble today. While unlikely, there are a couple more scenarios to keep in mind as you prepare to head into the mountains:

  • Loose snow avalanches: The mountains closest to Galena Summit (Salmon River Headwaters area) may have received several inches of very low-density snowfall yesterday. Also, the upper foot of the snowpack is extremely weak and faceted on some NW-N-NE-E facing slopes throughout this zone. On very steep slopes approaching 40 degrees, it won't take much to get surficial sluffs moving (photo). These may not be big enough to bury you, but they could knock you over and push you where you don't want to go.  
  • "Rogue" persistent slab avalanches: Triggering a larger avalanche on weak, sugary faceted snow deeper in the snowpack would take some seriously bad luck. To minimize the odds of this scenario, you can avoid very steep (over about 35 degrees) slopes with variable snowpack depths (rocks poking through the snow surface) that also have large, hard wind features that keep you on the snow surface. Watch this video to see what this setup looks like (video). 

Even small avalanches can ruin your day in complex, high-consequence terrain. Before committing to skiing or riding that steep, beautiful-looking line, think about where an avalanche could carry you. Could you get pushed over cliffs, through trees, or into a creek or gully? Slopes with these terrain traps are inherently more dangerous than open slopes with a clean runout. 

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