Avalanche forecast

Tetons

Bridger-Teton Avalanche Center
View on map

Avalanche danger

Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
Open full map
Out of date — this forecast expired 9 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Skiers and riders venturing into steep, wind-loaded terrain at the higher elevations could trigger small to large wind slabs. Above 7,500 feet, large to very large persistent deep slabs lurk on a variety of aspects. With afternoon snowfall and strong winds throughout the day, the likelihood of triggering both wind slabs and persistent deep slabs could increase as the day progresses. Monitor weather conditions and be willing to back off of high elevation terrain if a rapid loading event occurs in the afternoon. Below 7,500 feet, backcountry travelers might be able to trigger an isolated pocket of slab in very steep ravines and gullies.

Avalanche problems

  • Deep Persistent Slabs

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

    Dangerous persistent deep slabs up to five feet in depth remain a concern on a variety of aspects above 7,500 feet. While large triggers, such as snowmobiles or the release of a wind slab, are more likely to cause failure of these slabs, the weight of a single person could still act as a trigger if a shallow weak zone is encountered. These slabs could propagate long distances and are likely to carry severe consequences to anyone involved.

  • Wind Slabs

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

    Strong southwesterly to westerly ridgetop winds have formed pockets of wind slab in leeward terrain at the upper elevations. The light density snowfall on Wednesday was followed by much heavier snow resulting in upside-down conditions. Skiers and riders could trigger newly and recently developed wind slabs in steep, wind-loaded terrain. These slabs could range in depth from 6 to 18 inches with failure occurring on sun crusts, density breaks or down to a layer of surface hoar buried on January 19th.

Avalanche Discussion

Northwesterly flow aloft will continue to bring periods of mountain snow and valley rain to the region overnight through Sunday. Overnight lows in the mountains will be in the low 20s before rising into the upper 20s in the afternoon. Westerly ridgetop winds will range from 20 to 30 miles per hour.The general avalanche hazard is expected to be MODERATE above 7,500 feet on Sunday. In steep, leeward terrain above 9,000 feet, skiers and riders could trigger dense wind slabs ranging in depth from 6 to 18 inches. The additional load of the dense snowfall since Friday may begin to increase the likelihood of triggering persistent deep slabs on a variety of aspects above 7,500 feet, particularly in the Tetons. While large triggers, such as snowmobiles or the release of a wind slab, are more likely to be able to cause failure of these slabs, the weight of a single person could still act as a trigger if a shallow weak zone is encountered. Additional snowfall and warming temperatures may increase the likelihood of triggering both wind slabs and persistent deep slabs, particularly on sunlit aspects if any extended periods of sunshine occurs. Below 7,500 feet, backcountry travelers might be able to trigger an isolated pocket of wet slab in very steep ravines and gullies.

Regions covered