Two avalanche problems will confront backcountry users today. At the mid and upper elevations, skiers and riders could trigger small to large wind slabs in steep, wind-loaded avalanche terrain. In upper elevation terrain that held snow from early October, very large persistent deep slabs might still be able to be human triggered. Evaluate the snowpack and terrain carefully. The snowpack is mostly stable at the lower elevations, and avalanches are unlikely.
South-southwesterly to northwesterly ridgetop winds have combined with recent snowfall to form wind slabs in leeward terrain above 7,500 feet. Skiers and riders could trigger these slides to depths of one to three feet on steep, wind-loaded slopes.
Backcountry travelers might still be able to impact weak, faceted snow near the base of the snowpack on westerly through northerly to easterly aspects above 9,000 feet. Large triggers, such as snowmobiles, are more likely to cause failure of this basal weak layer. Previous tracks are not an indication of stability with a persistent deep slab problem. These dangerous and destructive slides could exceed six feet in depth and are likely unsurvivable.
Expect mostly dry conditions overnight before a cold weather disturbance drops out of western Canada and moves through the region on Sunday. Cloud cover will increase, and light snow showers will begin to develop after midday. Overnight lows in the mountains will be in the single digits before rising into the low teens in the afternoon. Southwesterly to westerly ridgetop winds will range from 10 to 20 miles per hour.The general avalanche hazard is expected to be MODERATE in the Teton and Greys River forecast zones on Sunday. In those areas, skiers and riders might be able to trigger a deep persistent slab on westerly through northerly to easterly aspects above 9,000 feet. Large triggers, such as snowmobiles, are more likely impact this basal weak layer, and previous tracks are not an indication of stability. Backcountry travelers could also trigger wind slabs to depths of three feet in steep, wind-loaded avalanche terrain above 7,500 feet. Snow depths in the Togwotee Pass area are shallower, and the basal weak layers are more easily impacted, which will keep the hazard at CONSIDERABLE. Wind slabs, similar to those in the other forecast zones, will continue to be a problem of concern.
