A six foot deep hard slab was reported to have occured on a southeast aspect of East Angle Mountain on Saturday. There are likely areas on both sides of the Continetal Divide where poor snowpack structure persist and these dangerous slides could be triggered by humans. Soft surface slabs with depths up to two feet could also be triggered by humans who venture onto steep slopes and have potential to step down and trigger a deep hard slab.
Dangerous hard slabs up to six feet in depth could be triggered on steep slopes where persistent layers of weak faceted snow exist within and/or near the base of the snowpack. These dangerous slabs could be triggered on slopes that have been crossed multiple times by other riders or skiers.
Dense surface slabs up to two feet in depth could be triggered by backcountry travelers who venture into steep avalanche starting zones and cliff areas. These slabs could step down and trigger dangerous persistent deep slabs in areas with poor snowpack structure.
( Discussion is generated from the previous day's afternoon forecast. )Colder air will move into the area overnight. Snow levels will fall to the valley level by morning. A slow clearing trend will occur on Tuesday with additional but diminishing mountain snowfall. Skies should begin to clear later in the day. Temperatures in the mountains will drop into the teens overnight and rise into the 20s during the day. Valleys temperatures should drop below freezing overnight and rise into the low to mid 30s during the day. West winds will veer to the northeast. Winds speeds of 25 to 35 with higher gusts will accompany the snowfall. On Tuesday new wind slabs that formed overnight are likely to be easily triggered by humans on steep wind loaded slopes and could attain depths of one to two feet. In areas with poor snowpack structure the potential for humans to trigger dangerous deep hard slabs will continue to be a concern. The general avalanche hazard is expected to be CONSIDERABLE in areas with poor snowpack structure (Greys River/Southwest Trails and Togwotee Pass/Continental Divide Areas) and MODERATE in locations where the threat of deep instabilities is limited to isolated areas.
