Some chance remains for backcountry travelers to trigger wind slabs in high elevation terrain or deep persistent slabs in steep terrain above 7500 where old buried weaknesses remain well preserved. Snowpack evaluation is necessary to see where this weakness continues to pose a threat. If predicted snowfall and strong northwest winds occur, new shallow surface slabs could develop and be sensitive in areas where they form upon hard crusts. Below 7500 feet significant avalanche activity is unlikely.
Deep persistent slab avalanches could be human triggered with depths of three to six feet. Initiation of one of these dangerous slabs my take a larger trigger, such as a snow machine, impacting a weak, thin spot on a slope.
Backcountry travelers venturing onto very steep, wind loaded slopes above 9,000 feet may be able to trigger slabs in steep terrain with depths of one to two feet.
( Discussion is generated from the previous day's afternoon forecast. )An approaching system from the northwest will combine with a system from the south tonight, causing rapidly increasing cloud cover. Snow will start to fall after midnight with just an inch or two of accumulation expected by sunrise. By tomorrow evening three to five inches of snow is expected in the Salt, Wyoming and Teton ranges, with two to three inches expected in the Togwotee Pass area. Temperatures in the mountains are expected to stay in the teens tomorrow. Winds are to be southwesterly overnight, veering to the north by Wednesday afternoon. Wind speeds could have averages in the twenties and gust into the forties or higher tomorrow. The General avalanche hazard will be Moderate in higher terrain and Low in lower terrain in all the forecast areas. In the Teton area, the slight chance of triggering wind slabs remains a possibility. In the Togwotee Pass area, where the snowpack is wrought with weak snow, deep persistent slabs could still be triggered by a single person, causing large to very avalanches. The Southwest Trails area has a potential for either of these avalanche problem types, wind slabs or deep slabs, although avalanches involving the deep weakness are not as probable as in the Togwotee Pass zone. In all areas, depending on snowfall amounts and wind speeds, new shallow wind slabs could form and be sensitive, particularly in areas where wind loading occurs on hard, slick crusts.
