Dangerous avalanche conditions are developing this morning at the mid and upper elevations. As the day progresses, the avalanche hazard will continue to increase as abundant snowfall and strong southwesterly to westerly winds add depth and volume to new wind slabs. Throughout the day, skiers and riders will be increasingly likely to trigger these slabs on steep, leeward slopes. Natural activity will also become possible. Travel in avalanche terrain will require expert snowpack and terrain evaluation skills. HIGH avalanche danger could develop this afternoon at the upper elevations. If so, travel in avalanche terrain is not recommended. Monitor the impact of the storm system and be willing to alter your travel plans if conditions warrant. At the lower elevations, backcountry travelers could trigger small pockets of wind slab in steep, wind loaded terrain.The Wyoming Department of Transportation will be closing Teton Pass for avalanche mitigation at noon. Parking is currently prohibited between the Idaho state line and the Wilson gate until mitigation efforts are concluded.
By this evening, developing wind slabs could reach depths up to three feet above 7,500 feet. As these slabs increase in size throughout the day, the chance for human triggering and natural activity will be on the rise in steep, wind loaded terrain. Below 7,500 feet, backcountry travelers could trigger similar slabs to depths up to 18 inches on very steep, leeward slopes.
Light snowfall is expected to continue through the evening. Increasing west-northwest winds will begin to subside after midnight. Scattered to isolated snow showers can be expected in the mountains on Monday. Skies should clear by the end of the day. Temperatures will drop into the single digits tonight and rise into the teens and 20’s during the day.Tonight’s winds will be creating soft slabs one to three deep on leeward slopes. These slabs are likely to sensitive to human triggers and plenty large enough to seriously injure and fully bury skiers and riders who venture onto steep avalanche prone slopes. The general avalanche hazard is expected to be considerable above an elevation of 8,000 feet and moderate below that elevation. Excellent terrain analysis skills and conservative terrain choices will be essential for safe travel in the backcountry.
