At the higher elevations new snow and strong southwest to west winds have increased the load on buried layers of crust and in isolated areas faceted snow that formed in October. Large slab avalanches are possible on these potential bed surfaces and could release naturally or be triggered by skiers or riders. These slab avalanches are anticipated to be two to four feet deep. If released they could bury, injure or kill a person. These dangerous conditions may extend into the mid elevations where these old October snow surfaces exist at the base of the snowpack. Avalanches are unlikely at the lower elevations. Hazards associated with a shallow early season snowpack are also prevalent at all elevations.
Large slab avalanches are possible on old snow surfaces at the upper elevations and on shaded aspects down to an elevation of 8,500 feet. Evaluate the snowpack to determine if these old snow problem layers could produce a dangerous slab avalanche.
After a brief lull this evening, northwesterly flow aloft will bring the next round of moisture to the region after midnight and continue through the day on Sunday. Overnight lows in the mountains will be around 10 degrees before rising into the mid-20s in the afternoon. Westerly to southwesterly ridgetop winds will range from 15 to 25 miles per hour.On Sunday, the general avalanche hazard is expected to be Considerable at the higher elevations in the Tetons. In steep, wind loaded terrain above 9,000 feet, skiers and riders could trigger slab avalanches with depths ranging from one to four feet. In the Togwotee Pass and Southwest Trails forecast zones, where storm totals are less, the general avalanche hazard in the mountains is expected to be Moderate. There, similar slab avalanches up to three feet deep could be triggered on steep, avalanche prone slopes. When evaluating the snowpack and terrain, be wary of slopes that held snow from October.
