Heavy snowfall and increasing winds will create dangerous conditions as the hazard rapidly increases to considerable. New soft slabs are likely to be sensitive to human triggers. Natural releases are possible. In areas with poor snow structure large slab avalanches could fail on buried persistent weak layers and step down through old snow layers. Expert snowpack evaluation and route selection skills are essential for safe travel in avalanche terrain.
Southwest winds will be forming new soft slabs on leeward aspects. These slabs will be forming on good sliding surfaces and are likely to be easily triggered by humans. They could release naturally with depths to two feet at the higher elevations and in pockets with depths to a foot at the lower elevations.
Persistent weak layers in the snowpack are being loaded. These layers may collapse and cause large slab avalanches that will be comprised of the new storm snow and older snow. These slabs could be 2 to 4 feet deep at the mid and upper elevations and up to two feet deep at the lower elevations. They could be triggered by the weight of a single person. Natural releases on these faceted problem layers are possible.
( Discussion is generated from the previous day's afternoon forecast. )A winter storm warming is in effect for the Teton Range and a winter weather advisory is in effect for the Salt River Range, Wyoming Range, Wind River Range and the western valleys for tonight through Friday morning.Light snowfall will continue over the region tonight and will increase in the morning and possibly become heavy by mid-morning. That snowfall will again become light to moderate in the afternoon and evening. Forecast snowfall amounts are 4 to 6 inches in the valleys, 6 to 10 inches in the mountain. Higher amounts are possible in the Teton Range. Temperatures will be in the teens and 20s. Winds will be from the southwest to west at 20 with gusts to 35 miles per hour.New snow and winds are expected to create dangerous avalanche conditions on steep slopes and increase the general avalanche hazard to considerable. New soft slabs are expected to grow to depths of 1 to 2 feet. These slabs are likely to be sensitive to human triggers and may release naturally. In steep areas with poor snow structure large slab avalanches that step down into the old snow and fail on persistent weak layers could be triggered by humans with depths from 2 to 4 feet. Monitor conditions for increasing hazards. Excellent snowpack evaluation and route selection skills will be essential for safe travel in avalanche terrain.
