Tetons

The general avalanche hazard will increase during the day. Pockets of hard and soft surface slab up to 18 inches deep were skier triggered or released naturally yesterday on south through northeasterly aspects above an elevation of 9,000 feet. At the upper elevations and northerly aspects of the mid elevations new snow and wind will load a snowpack with weak layers that have demonstrated instabilities. The potential for humans to triggered slab avalanches one to two feet deep will increase as the day progresses. The potential for natural avalanche activity to occur must be closely monitored if rapid loading is observed. Only shallow loose snow sloughs are expected on very steep slopes at the lower elevations where the existing snowpack is less than a foot deep.

A winter storm warning was issued for the Western Mountains and Valleys of Wyoming by the National Weather Service at noon and is in effect until Sunday Evening . The winter storm that has moved in from the Pacific is forecast to intensify and bring periods of moderate to heavy snowfall accompanied by strong winds through tonight, on Sunday and into Sunday Evening. Storm totals are expected to be one to two feet in the Mountains, up to three feet in the Teton Range and six to 12 inches at the lower elevations. Temperatures will remain in the teens in the mountains and should approach 30 degrees in the valleys on Sunday. Winds along the highest ridge crests will continue to be southwesterly at 20 to 30 miles per hour with higher gusts. With one to two feet of new snow and strong winds forecast during the next 24 hours the general avalanche hazard will increase to HIGH at the upper elevations of the Teton and Greys River/Southwest Trails forecast areas. It will increase to CONSIDERABLE at the mid elevations of these forecast areas and at the mid and upper elevations of the Togwotee Pass/Continental Divide area. The general avalanche hazard in all areas below an elevation of 7,500 is expected to remain LOW. Travel in avalanche terrain at the upper elevations of the Teton and Greys River areas is not recommended. Excellent terrain evaluation skills are essential for safe travel in avalanche terrain at the mid elevations of the Teton and Greys River area and the mid and upper elevations of the Togwotee Pass area. In all forecast areas above an elevation of 7,500 feet, soft slab avalanches one to three deep are likely to be easily triggered by humans. Natural avalanches are likely.