Tetons

Several days of melt-freeze cycles have progressed the snowpack to a point where the avalanche danger is Low this morning and will increase to Moderate in the afternoon. Remember that low hazard does not mean no hazard exists and backcountry travelers should be wary this morning of the potential for small avalanches in very steep or extreme terrain. Rapidly rising temperatures and direct sunlight will quickly break down surface crusts and weaken the upper portion of the snowpack. This will allow for the possibility of human triggered slab avalanches at the mid and upper elevations this afternoon with depths that could reach four feet. These lingering instabilities will be most likely to be found in steep avalanche terrain around cliff areas. Wet slides will also become possible on south facing terrain at all elevations and natural activity could occur in shallow very steep terrain at low elevations such as on road cuts.

Overnight, temperatures are expected to drop into the teens in the mountains and single digits in the valleys. The day will start with clear skies. Then, as a Pacific disturbance passes over the region, cloud cover will increase, and there is a slight chance for light precipitation. The high temperatures are expected to be in the upper 30s in the mountains and 40s in the valleys. Southerly to southwesterly ridgetop winds will be 10 to 20 in the morning and increase in the afternoon. In the Grey’s River and Togwotee Pass forecast areas, deep persistent slab avalanches, up to 8 feet deep, still pose a threat. While the avalanche hazard in these forecast areas has slowly decreased, it is still possible for a person to trigger a very large slab avalanche, and if this occurs, the consequences would likely be fatal. In the Teton forecast area, large slab avalanches have become unlikely, although as the day warms the potential for triggering slab avalanches up to 4 feet deep will be possible. The avalanche hazard is expected to be Moderate in all three forecast areas tomorrow. Daily warming will increase the potential of triggering an avalanche, weaken cornices, and could cause wet slides. Backcountry travelers should use careful evaluation of the snowpack and terrain to travel safely through the mountains.