Avalanche forecast

Sawtooth & Western Smoky Mtns

Sawtooth Avalanche Center
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Avalanche danger

Wed
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Out of date — this forecast expired 6 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Dangerous avalanche conditions exist. Triggering an avalanche that fails on weak snow buried 2+' deep remains likely on most slopes—especially in wind-drifted terrain. Avalanches may be triggered remotely—from below, above, and to the sides of steep slopes. Skiers and riders remotely triggered avalanches in neighboring zones 3 out of the past 4 days.

Avalanche problems

  • Persistent Slabs

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

    In the past month, a thick layer of weak snow has been incrementally loaded across our entire Forecast Area. With each major loading event we've observed widespread avalanche activity and a pattern of human-triggered avalanches extending many days after loading. This layer can be found 1.5-2.5' beneath the snow surface.

    On Saturday, near Galena Summit, skiers remotely triggered a 1.5-2' thick avalanche from low angle terrain (photo below/right, more details). I visited the site of this avalanche the next day (video here) and found a very similar snowpack to that found in the southern portions of the Sawtooth and Western Smoky Mtns Zone. On Sunday, across the valley in the Pole Creek drainage, a group of riders remotely triggered an avalanche that buried the road they were riding on. This happened after the 4th rider had passed underneath the starting zone above. Both of these avalanches paint a good picture of the type of conditions that exist in the backcountry right now.

    Conditions remain dangerous today, it's likely you could trigger a large avalanche on most steep slopes. The best—and often only—way to manage a persistent slab problem is by sticking to lower-angled terrain. Given the possibility of remote-triggering, you'll also want to avoid being below steep slopes. 

Avalanche Discussion

One important variable that we consider when assessing avalanche hazard is the amount of time that has elapsed since a load was placed on the snowpack. In our case, the last major snowfall occurred six days ago. Following this storm, strong to extreme winds easily pushed around the snow that fell. In some places, winds were strong enough to blow the snow off into the atmosphere while in others it loaded slopes. This additional loading produced a second round of natural avalanche activity. It has now been a few days since we've observed active wind-loading, which has given the snowpack a bit of time to adjust to the additional stress.

Generally, a few days without loading is a healthy break for the snowpack. If we were dealing with a strong snowpack without weak layers, the avalanche hazard would lower right now. However, the sugary, faceted snow buried near the ground in our region is anything but strong. This widespread layer of weak snow has been buried for over a month, and each time we add more weight with a storm we see widespread natural avalanche activity. Equally importantly, each time we add a trigger to the mix (riders, skiers, you!) we are seeing human-triggered avalanches continue many days after loading. Our snowpack doesn't need a weekend off, it needs a long vacation on the beach. 

The backcountry is what is known as a "wicked learning environment." Environments like this provide feedback that is either difficult to interpret or altogether nonexistent. For example, your partner decides to ski a steeper line than you had agreed upon and nothing bad happens. Does that mean that the slope was actually safe and that the decision was a good one? Well, no. And therein lies the problem—the only direct feedback that we get from the snow is when it avalanches. The absence of an avalanche is not a sign of stability. And once we trigger an avalanche we have set ourselves up to learn some hard lessons.

Today will be a beautiful, calm, sunny day. The lure of steep, untracked slopes will be strong. But the weak snow that is buried in our snowpack is not in any hurry to heal and today is not significantly safer than yesterday. We continue to encourage you to make your decisions in the backcountry with this weak snow in mind.

Regions covered