Recent storms brought approximately two feet of snow to upper elevations of the Tetons. Strong winds yesterday that ranged from the south-southwest to the west formed wind slabs at all elevations. These slabs were sensitive to backcountry travelers yesterday and also released naturally. In the Tetons, skiers triggered a slab in Drew's slide to the south of the Jackson Hole Mountain resort and in Hoback Canyon, Cow of the Woods slide released naturally, depositing ten feet of snow on the road. Although natural activity has become unlikely, these recently formed slabs could fail to the weight of a single person in steep wind loaded areas at all elevations, particularly this afternoon when they are further weakened by sunshine and increasing temperatures. Deeper in the snowpack, older weak layers remain a concern. Slabs involving these deeper layers will be larger and could initiate as the result of a triggered surface slab or when a particularly weak spot in the snowpack is impacted. Exercise conservative decision making in steep terrain and do not allow a nice sunny day lure your group into terrain where recently formed slabs remain unstable.
Recently formed slabs lie in steep wind loaded terrain on a variety of aspects with depths to three feet at higher elevations and to eighteen inches at lower elevations. These slabs will increase in sensitivity as they are weakened by sunlight and warming temperatures.
The chance continues for large to very large avalanches involving old weak snow layers be triggered at the mid and upper elevations with depths to five feet.
Clouds that are to pass through the area tonight may provide a few flurries or a brief period of light snow to the mountains. Wednesday looks to be dry with partly to mostly cloudy skies. Inversion conditions will allow mountain temperatures to range from morning lows in the teens to highs in the upper twenties in the afternoon. Valleys should start near zero degrees before rising into the thirties. Winds are to be light and variable. The general avalanche hazard will be Moderate at all elevations. Above 8000 feet, recently formed wind slabs have become less likely to fail. However in very steep wind loaded terrain, particularly in cliff areas where the slabs are unsupported, skiers or riders could still trigger them to depths of three feet. Also at the higher elevations, large avalanches involving persistent weak layers deeper in the snowpack have some potential to occur. Triggering these deeper layers is likely to take lake a larger impact such as the initiation of a surface slab or a group of people, although in some areas a single person hitting a weak spot could cause failure, particularly in steep areas where the snowpack is shallow. At lower elevations, the potential continues to trigger pockets of slab where recently wind loaded snow lies over a generally weak snowpack.
