Tetons

Clear skies overnight fostered radiant cooling which resulted in frozen snow surfaces and a mostly stable snowpack. With mountain temperatures starting out 5 to 10 degrees warmer than yesterday, the threat of shallow wet slides could return before noon on sunlit aspects at the mid and upper elevations. Get an early start, monitor the sun’s impact on snow surfaces, and begin to transition to cooler terrain when surface crusts start to break down. At the higher elevations, skiers and riders might still be able to trigger an isolated pocket of wind slab up to a foot deep on very steep, avalanche prone slopes that have not been significantly affected by the sun. This hazard is likely to be more widespread in the cooler terrain above 10,500 feet. The lower elevation snowpack, which is becoming sparse and has undergone numerous melt freeze cycles, is mostly resistant to wet slides.

Southwesterly flow aloft will continue on Friday with the main jet just to the northwest of the region. An embedded Pacific weather disturbance and associated cold front will brush the region bringing a chance for precipitation starting this evening and continuing into Friday morning. A second, weaker system will move through in the afternoon. Overnight lows in the mountains will be in the low 20s before rising into the upper 20s during the day. By Friday morning, valley temperatures will drop to near freezing before climbing into the low 40s in the afternoon. Southerly to southwesterly ridgetop winds will range from 25 to 35 miles per hour with gusts into the 40s.The general avalanche hazard is expected to be LOW Friday morning if only modest amounts of snowfall accumulate overnight. Strong ridgetop winds will begin to form isolated pockets of shallow wind slab in leeward terrain near upper elevation ridgelines. These slabs will gain depth and volume commensurate with the amount of additional snowfall during the day. With colder temperatures and cloud cover, the threat of wet slides will be significantly diminished. At the higher elevations, skiers and riders might still be able to trigger an isolated pocket of shallow wind slab involving snowfall from last week on very steep, avalanche prone slopes that have not been significantly affected by the sun. This hazard is likely to be more widespread in the cooler terrain above 10,500 feet.