Avalanche forecast

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Sawtooth Avalanche Center
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Avalanche danger

Sun
Alpine
2 · Moderate
Treeline
1 · Low
Below
1 · Low
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Out of date — this forecast expired 7 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Triggering a large avalanche is unlikely.  Unstable slopes are becoming few and far between, but triggering a 3-5 foot thick avalanche may be possible on very steep, rocky, wind-affected slopes at upper elevations. Smaller—but more likely—problems to watch for include fresh wind drifts on high ridges and wet sluffs on steep, sunny slopes.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    2–3

    Triggering a 3-5 foot thick persistent slab avalanche is unlikely. The weak layers we've struggled with all winter have not gone away, but the last part of January has given them the breather they've needed to become less reactive to the weight of a skier or rider. 

    Are there still slopes where it remains possible to trigger these layers? Probably, but it would likely take a dose of bad luck to find them. Deeply buried weak layers are difficult to trigger, and shallow areas are often needed to impact the weak layer. But don't completely write them off—especially since the consequences of a triggering a 3-5 foot thick persistent slab would be catastrophic.

    If you wanted to hunt down one of these elusive persistent slabs, here's where I would look: upper elevation and alpine, rocky, wind-affected terrain steeper than about 35 degrees.  But I'd speak softly and carry a big stick.

    ADDITIONAL DISCUSSIONIn addition to the persistent slab problem above, there are smaller—but more likely—problems you should also keep on your radar:

    • As a result of moderate to strong winds yesterday and today, you may find fresh, sensitive wind slabs and drifts in upper elevation terrain. 
    • With warm temps and sunshine the past few days, most of the wet avalanche activity may have already come and gone. But watch for wet sluffs on steep, sunny slopes during the heat of the day.

Avalanche Discussion

With much of the forecast area trending towards Low avalanche danger, this is a nerve-wracking time to be an avalanche forecaster. This rings especially true with widespread persistent weak layers in the snowpack. Decreasing danger usually leads to more folks riding in steep terrain, which means more people testing your theory of the snowpack stability.

Our theory is that the persistent weak layers have had some time to adjust to the load from the first part of January. Especially in our northern and western mountains, they are buried deeply enough to be difficult to trigger. The weak layers aren't gone, they're just trending towards what we call dormancy and we probably haven't seen the last of them. The last slopes to stabilize in this scenario are usually the "baddest of the bad"—upper elevation/alpine, rocky, wind-loaded terrain steeper than 35 degrees. It would still take some bad luck to trigger an avalanche in these areas, but it's certainly not outside the realm of possibility.

The danger scale is a very general description of the overall avalanche conditions. If you've read this far, you likely know that there are more subtleties and nuances to the avalanche danger than can be summed up by one word. As the avalanche danger continues to drop, we hope folks will keep in mind the weak layers under your boards or sled—even if they lie dormant for the moment. If forced to choose between Low danger with persistent weak layers, and Low danger without, I'd choose without each and every time.

Regions covered