If extended periods of sunshine occur, the threat of wet slides could return as the day warms. In very steep, wind-loaded terrain above 8,000 feet that has not gone through melt-freeze cycles, skiers and riders might be able to trigger an isolated pocket of wind slab up to 18 inches deep. Monitor weather conditions, and move to shaded terrain if surface crusts begin to break down.
Cloud cover overnight kept temperatures fairly warm. If extended periods of sunshine occur during the day, wet slides will once again become possible. These slides are mostly likely to occur in very steep terrain at the mid and lower elevations where nightly lows were near freezing, and daytime temperatures will be the warmest.
The National Weather Service has issued a Winter Storm Warning for the Tetons and Gros Ventre Mountains beginning at 5 AM Sunday morning and continuing through 5 PM on Monday. During this same time period, the surrounding areas will be under a Winter Weather Advisory. Snowfall will develop overnight and continue through the day as moist, westerly flow resides over the region. Nighttime lows in the mountains will be in the teens before rising into the 20s during the day. Westerly ridgetop winds will range from 25 to 35 miles per hour with gusts to near 50.The general avalanche hazard is expected to increase to Moderate on Sunday. Wind slabs, which will form on stout sun crusts and wind pack, could be triggered by skiers and riders venturing in steep avalanche terrain. As the day progresses, these slabs will gain depth and volume. In the Togwotee Pass area, persistent weak layers deeper in the snowpack will remain a concern.
