Significant snow fell at the mid and upper elevations of Tetons. Skiers and riders could trigger soft slabs today in steep avalanche terrain, particularly where wind loading has been the most significant. These slabs will be most sensitive at the high elevations where any moving snow could quickly involve large volumes of powder. Cautious route finding and careful snowpack evaluation is advised. A slight chance also remains for a large trigger to cause failure of weak snow near the base of the snowpack, resulting in large to very large avalanches. Avalanches at low elevations are unlikely today.
At the mid and upper elevations, southwest winds during peak snowfall that have been veering to the northwest have formed soft slabs with depths to two feet. These slabs could be human triggered this morning and may increase in sensitivity in areas where they are rapidly warmed by direct sunlight and increasing temperatures.
Although unlikely, a slight chance still exists to trigger deep hard slabs involving weak snow near the base of the snowpack. If triggered these slabs could have crown depths of 3 to 7 feet. Larger triggers such as a cornice drop, a moving wind slab or a snowmachine hitting a thin spot on a slope may be required to trigger such an event. Involvement in one of these slides would likely be fatal.
The next Pacific system will be dropping south in a northwest flow tonight. It will spread light snowfall into the region. Accumulations of 1 to 3 inches are likely overnight. Skies are expected to gradually clear after 9 am and become mostly sunny in the afternoon and evening. Temperatures will rise into the 20's. Winds will be from the north-northwest at 5 to 15 with gusts to 25 miles per hour.The general avalanche hazard is expected to be moderate at the mid and upper elevations (7,500 to 10.500 feet). Up there, skiers and riders could trigger soft slab avalanches on steep slopes. These surface slabs could be up to two feet deep. These slides will be large enough to hurt or bury a person and will be especially hazardous in steep chutes, couloirs, cliff areas and above terrain traps. Deep persistent slab avalanches are still a concern. These dangerous slides could be 3 to 7 feet deep and could fail due to the weight of a snowmachine, the release of a surface slab or when a skier or rider on a steep avalanche prone slope crosses a thin area of a persistent slab. The general avalanche hazard at the lower elevations is expected to be low.
