Avalanche forecast

Soldier & Wood River Valley Mtns

Sawtooth Avalanche Center
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Avalanche danger

Tue
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
2 · Moderate
Out of date — this forecast expired 5 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Dangerous avalanche conditions will continue to develop over the course of the day. Your likelihood of encountering an avalanche is much higher on slopes that held snow prior to this storm and in areas where the wind has built slabs. This terrain is most common in the western portion of this zone (Soldier Mountains) and in the upper reaches of places like Bald mountain. In these areas, large human-triggered avalanches are likely.

Avalanche problems

  • Wind Slabs

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

    As of 5 AM this morning, much less snow has fallen in this zone than in our other forecast areas. You are most likely to encounter dangerous avalanche conditions in upper elevation terrain that is wind-loaded. Slides are much more likely on slopes that held snow prior to this storm—those located roughly on the northern half of the compass. Look for obvious signs of wind transported snow such as dunes and drifts, ripples on the snow surface, and recently formed cornices. Use your hands, poles, and skis to feel for changes in the density and texture of the snow. All of these observations will help you to identify areas where the wind has been at work building slabs. Human-triggered avalanches are likely in these areas.

    Additional discussion: While you are most likely to encounter slabs in wind-loaded terrain, avalanches are possible in sheltered terrain as well. An ugly mix of crusts and facets developed during the long drought. This type of snow can fail in ways that surprise even very experienced users. Slabs that release on facets can fail in surprising ways, often breaking wider than you might expect and wrapping around terrain features. They also may be triggered remotely—from a distance above, below, or to the sides of steeper slopes.

Avalanche Discussion

SPATIAL VARIABILITY AND UNCERTAINTY Avalanche forecasting is rarely simple and clear-cut. That is particularly true on mornings like today. There is a high degree of spatial variability out there, both in the presence and nature of pre-existing snow coverage and in the distribution of snowfall during this storm. Early-season snowfall followed by a long period of above-average (occasionally record-setting) temperatures left us with a highly variable snowpack. Many slopes that face the sun directly lost their snow coverage entirely while shaded slopes at middle and upper elevations developed an ugly mix of slick crusts and facets. The new snow will make it much more difficult to determine which slopes did or did not keep their early season snow. As you move from a slope that was dry two days ago to one that has been holding snow for a month and a half, avalanche conditions will change significantly. This can happen over the span of hundreds of feet or less.

Storm slabs, wind slabs, persistent slabs, loose snow avalanches and cornices...you're going to find it all today if you go looking for it. When we have a high degree of variability and overlapping patterns of old snow, new snow, and wind transported snow, it becomes very difficult to safely navigate avalanche terrain. Add to that the fact that visibility will be poor and your snowpack assessment and terrain management skills are almost certain to be rusty and you have plenty of reasons to dial back your ambition and to stay conservative in your terrain selection. 

Regions covered