The general avalanche hazard is considerable above an elevation of 8,000 feet and is moderate below that elevation. Dangerous slab avalanches could be triggered by snowmachines and skiers. In areas that have exhibited poor snow structure for several months large to very large persistent slab avalanches could be triggered by the weight of a single person or after a slope has been crossed multiple times by snowmachines. Slab avalanches could be triggered by humans in wind loaded areas, involving snow from the recent storm cycle or they could fail on well-developed weak layers comprised of faceted snow that formed during prolonged dry periods earlier in the season. Careful snowpack evaluation is necessary to understand the weak snowpack and conservative decision making is essential to avoid having accidents that are likely to have severe consequences.
Surface slabs formed during the most recent storm cycle continue to be a potential hazard on steep, wind-loaded slopes at the higher elevations. These slabs could be triggered by the weight of a single person and could be one to three feet deep.
In steep terrain persistent slab avalanches could be triggered by humans on buried layers of faceted snow. These slabs could be triggered by a single person who crosses a weak spot on a slope, by larger triggers like snowmachines or by the initiation of a wind slab. These large to very large slab avalanches could be 3 to 5 feet deep at the mid and upper elevations or one to three feet deep at the lower elevations.
( Discussion is generated from the previous day's afternoon forecast. )Periods of light snow or flurries are likely until around midnight. After a brief respite light snowfall will return to the southern portion of our forecast area on Thursday afternoon. Temperatures will be in the single digits above and below zero overnight. Daytime highs will rise into the positive single digits and teens in the mountains and into the 20s in the valleys. Winds are forecast to be light and variable.Humans who venture onto steep avalanche prone slopes could triggered surface slabs one to three deep that were formed during the past storm cycle and persistent slabs with depths of three to five feet that lie upon weak layers that formed earlier in the season. These dangerous persistent slabs are most likely to be triggered in areas that have exhibited poor snow structure for several months. Although there may be slopes where large slides can still be triggered by the weight of a single person these slabs may be more likely to be triggered by snowmachines. The general avalanche hazard is expected to be moderate in the Teton and Greys River/Southwest Trails areas and considerable in the Togwotee Pass area.
