Avalanche forecast

Tetons

Bridger-Teton Avalanche Center
View on map

Avalanche danger

Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
Open full map
Out of date — this forecast expired 11 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Snowfall densities increased from five percent to ten percent over the last few days, which have created an upside-down snowpack. Two human triggered slides occurred yesterday in backcountry to the south of the Jackson Hole Mountain Resort, and both resulted in skiers and riders being captured. Luckily no one was fully buried or injured. Similar soft wind slabs are likely today in steep, wind-loaded terrain. In more sheltered areas, loose snow sluffs are also possible. These slides also have the potential to step down to faceted snow near the base of the snowpack above 7,500 feet. As the day warms, these slides could become more susceptible to failure on sunlit aspects if any extended periods of sunshine occur. A conservative approach to both terrain selection and decision making will be essential for safe travel in avalanche terrain today.

Avalanche problems

  • Wind Slabs

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

    Skiers and riders could easily trigger new and recently developed soft wind slabs on all aspects and elevations. At the higher elevations, these slabs could have depths of one to three feet and fail on old hard surfaces or density breaks within the recent snowfall. At the lower elevations, they lie upon faceted snow and could release up to 18 inches deep. Beware of steep terrain with obvious areas of wind loading. Several of these wind slabs have been reported in recent days on a variety of aspects and elevations.

  • Deep Persistent Slabs

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

    Above 7,500 feet, hard slabs with depths to six feet lie upon persistent weak layers of faceted snow. Since Wednesday night, over four inches of snow water equivalent have been added to the snowpack. Large triggers, such as groups of people, may be needed to trigger one of these slides. The release of a wind slab could also step down to these basal facets. If triggered, these slabs will carry high consequences.

Avalanche Discussion

Another system is to bring snow tonight and Wednesday. The National Weather Service has issued a winter weather advisory. A foot of new snow is possible at the higher elevations by Thursday and this snowfall is to be accompanied by strong west winds. Mountain temperatures are to reach near twenty degrees on Wednesday. The general avalanche hazard is expected to be Considerable at the mid and high elevations on Wednesday. By the afternoon, the hazard could raise to HIGH above 9000 feet as natural avalanche activity becomes likely from the new snowfall and strong west winds. The avalanche problems includes new and recently formed wind slabs to 3 foot depths as well as persistent weaknesses which could result in large dangerous slabs to six foot depths in the Tetons or lesser depths in the Southwest Trails or Togwotee Pass areas. Below 7500 the avalanche hazard is expected to be Moderate in the morning and could rise to Considerable in the afternoon depending on snowfall amounts at the lower elevations. Given the amount of loading over the last week and the forecasted heavy snowfall to come, cautious route finding and decision making are essential during this period. Known avalanche paths should simply be avoided and safer, low angle, conservative terrain should be the focus of backcountry travelers.

Regions covered