In areas that still have poor snow structure 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. These dangerous slabs will fail on well-developed weak layers comprised of faceted snow that formed during prolonged dry periods earlier in the season. Smaller slab avalanches could also be triggered snow snowmachines and skiers in steep wind loaded avalanche starting zones where snow have been recently drifted. A careful evaluation of the snowpack is necessary to identify areas with inherent weaknesses. Conservative terrain choices are essential to avoid having accidents which are likely to have severe consequences. The general avalanche hazard is considerable above an elevation of 8,000 feet and is moderate below that elevation.
Surface slabs formed by recent winds could be triggered by the weight of a single person. These wind slabs could be one to two 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. )Tonight will be mostly dry, calm with periods of clear skies. Temperatures will be below zero. Skies will be mostly clear in the morning and partly cloudy in the afternoon. Easterly winds will back to the northeast and then towards the west.Slab avalanches could be human triggered on steep slopes. Large, persistent slab avalanches that are 3 to 5 feet deep continue to be a threat especially in areas where the snowpack is shallower and has poor structure. Surface slabs up to 3 feet deep could also be triggered by humans in very steep avalanche starting zones. Identify and avoid steep, wind loaded terrain features and evaluate the snowpack carefully to determine where old weaknesses still pose a threat. The general avalanche hazard is expected to be moderate in the Teton and Greys River/Southwest Trails areas and considerable above an elevation of 8,000 feet in the Togwotee Pass area.
