An avalanche warning is in effect. Large avalanches were explosively triggered on Teton Pass early this morning and impacted the highway. Natural and human triggered avalanches are likely today. Travel in avalanche terrain is not recommended.
At the mid and upper elevations persistent slabs up to five feet in depth lie upon a base of weak, faceted snow. New snow and winds will be loading these dangerous slabs and increasing the potential for these slabs to be human triggered or release naturally. These destructive slab avalanches could run long distances.
Southwest winds and heavy snowfall have created new soft slabs up to three feet in depth. These slab could release naturally or be human triggered and run long distances.
Snowfall will continue overnight and into the day with another five to ten inches of accumulation possible by Thursday morning. Winds will be west to southwest at 15 to 25 miles per hour with higher gusts. Temperatures will be in the single digits and teens at 10,000 feet and in the teens and low 20s in the valleys. A large load has been placed on a snowpack with poor structure. Gusty winds will continue to load leeward slopes. Dangerous unstable conditions exist, especially in areas where extensive faceted old snow persists beneath the new snow that has accumulated during the past 10 days. Large human triggered slab avalanches are likely. Natural avalanche activity is possible. The general avalanche hazard is expected to be HIGH in the Togwotee Pass and the Greys River areas and CONSIDERABLE in the Teton area.
