The mountains have received 6 to 9 inches of new snow with close to a half-inch of water since Thursday morning. Humans who venture onto steep avalanche prone slopes at the higher elevations could trigger soft slab avalanches and loose snow sluffs. This new snow and wind has also increased the load on persistent weak layers. This new load may increase the potential for humans to trigger large persistent slab avalanches. Avalanches are unlikely below an elevation of 7,500 feet. A careful evaluation of the snowpack and terrain is warranted. Practice safe travel techniques.
Skiers and riders could trigger large persistent slab avalanches on buried weak layers of surface hoar and faceted snow. The slab slabs could also be triggered by the release of a fresh wind slab or a sizable loose snow avalance. These persistent slab avalanches could be two to four feet deep.
( Discussion is generated from the previous day's afternoon forecast. )As the leading edge of a trough moves into Nevada and Utah, precipitation will draw to the south. Snowfall will continue across the region overnight and into tomorrow. The low-pressure system is only expected to affect the southern portion of the forecast area, where the National Weather Service has issued a winter weather advisory for tomorrow. The Salt River and Wyoming Ranges could receive 6 to 10 inches of snow. While in the Togwotee Pass and in the Teton forecast areas, snowfall is expected to be light with about an inch of accumulation through tomorrow. Winds across the region are expected to remain light and variable, and mountain temperatures will start in the teens rising into the twenties. As the storm impacts the Grey’s River area, the additional load on buried persistent weak layers could increase the avalanche hazard causing these persistent slabs to become more sensitive to triggers. It remains possible for riders and skiers to trigger avalanches, up to five feet in depth, in steep avalanche-prone terrain. Due to the large size of these avalanches, dangerous avalanche conditions exist, and the avalanche hazard is expected to be Considerable. Across all the forecast areas, shallow wind slabs 1 to 2 feet in depth and loose snow sluffs involving the new snow remains a concern on steep slopes.In the Teton and Togwotee Pass areas, the avalanche hazard is expected to be Moderate. On Togwotee Pass, persistent slab avalanches, with slab depth of 2 to 4 feet, could be triggered by riders and skiers. While in the Tetons, there is still some concern with the persistent slab in areas where the snowpack is shallow, the15 inches of new snow is more likely to get backcountry travelers into trouble.
