Avalanche forecast

Sawtooth & Western Smoky Mtns

Sawtooth Avalanche Center
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Avalanche danger

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

You could trigger wind drifts in exposed, upper elevation terrain. Some drifts overlie crusts and weak faceted snow that formed before the last storm, making wider avalanches possible.  As the sun warms the snow surface, expect natural loose snow avalanches in steep, rocky terrain directly facing the sun. It'd be a stroke of bad luck, but triggering an avalanche on weak layers buried 4-6 feet deep remains a possibility on very steep, rocky, wind-affected slopes at upper elevations. 

Avalanche problems

  • Wind Slabs

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

    Wind slabs that formed in the past few days remain a concern in exposed terrain, especially at upper elevations. The slabs and drifts buried a variable old snow surface, including wind-hammered snow, crusts, facets, and about anything else you can imagine. The pattern of recent natural avalanche activity has favored slopes on the eastern and western margins of the compass; our snowpack observations indicate those aspects have a crust+facet combination that appears to be more sensitive than other subsurfaces. 

    Look for signs of wind affected snow such as dune-like drifts and ripples on the snow surface as you travel. The wind-driven surface textures can be large or small. Also, today's sunshine could cause small loose snow avalanches (see Problem 2 below) that have the potential to trigger slab avalanches lower on slopes. Be aware of what's above you. 

    ADDITIONAL DISCUSSIONTriggering a 4-6 foot thick persistent slab avalanche is unlikely. It would take a dose of very bad luck, but it may be possible to trigger one of these monsters in very steep (over 35 degrees), wind-swept, alpine terrain.  

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    With a healthy dose of unobstructed sunshine in the weather forecast, we may see some small, natural loose snow avalanches. Cold temperatures will counter the sun's effects but will not eliminate the loose snow avalanche problem. The threat of loose snow slides will follow the sun around the compass: initially on E-SE aspects this morning, moving to S-facing slopes by noon, and finishing on W-SW aspects later in the afternoon. Stability can change quickly; think minutes rather than hours. 

    The warming is most pronounced in very steep, rocky terrain with an alpine flavor. Small sluffs could trigger soft slabs as they pick up speed and travel downslope. Be aware of the terrain above you. Find safe, protected spots free of overhead hazard for your extended breaks to eat lunch or bask in the sun.  

Avalanche Discussion

We have a few problems to consider today. Fortunately, they can be managed fairly easily with standard safe travel procedures. Let's have a quick review:

Wind Slabs: As described above, you may find small wind slabs that formed over the weekend. They should be relatively small and easy to spot and avoid.  

Cornices:  This photo shows some large, overhanging cornice growth near Copper Mountain, representative of this zone. Cornices are unpredictable beasts and can break much farther from the "lip" or edge than you'd expect. Give them some space, especially if you aren't excited about the prospects of rolling down whatever slope is beneath them. 

Loose Snow: Loose snow avalanches are typically divided into dry and wet categories, but there are a hundred shades of grey between these two. Today, we will probably see small slides that fit in the wet/dry loose snow avalanche boxes as well as slides that blur the lines. If you are skiing or riding in very steep, shady terrain, dry loose slides are on the table. As you wrap around to the southern half of the compass, sluffs that start because the sun is warming the snow surface but end up picking up dry snow underneath as they travel downslope are also possible. Today, both natural and human triggered, "sun-induced" sluffs are possible.

All of these problems are simpler to manage than persistent slab avalanches but can be consequential in the wrong terrain. If you are caught and carried through rocks and cliffs, it doesn't really matter if the avalanche is large enough to bury you or not. Have fun in the sun, but be aware of the terrain above and below you.  

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