Tetons

Dangerous avalanche conditions continue to be a threat to backcountry travelers. Yesterday, a skier was buried by a small slide in the Teton Pass area and similar events could happen today. Over the last seven days a consistent pattern of storm systems has brought approximately thirty inches of snow and three inches of snow water equivalent to the higher elevations of the Tetons. A chance continues to trigger wind formed slabs within this new snow, however, the primary concern rests with persistent weak layers of snow that lie at the interface of this recent snow that started falling last Tuesday or within deeper weak layers formed during previous cold dry periods. These instabilities could be triggered at all elevations today and have the potential to be large at the mid and upper elevations. Conservative terrain choices are necessary to avoid this persistent slab problem.

The incoming system will bring snowfall to the area by midnight with a few inches expected by sunrise. Steady snowfall is to continue through the daylight hours and the evening. Five to ten inches is expected by midnight with higher amounts expected in the upper elevations of the Tetons. West winds are to average near twenty to twenty-five miles per hour while mountain temperatures have highs in the mid-teens. The general avalanche hazard is expected to remain Considerable above 7500 feet and Moderate below that elevation. At all elevations, backcountry riders and skiers have the potential to trigger slab avalanches involving persistent weak layers of snow involving surface hoar and in many areas profoundly faceted layers. These slabs could be released remotely or once a person is on a slab and finds a weak point on the slope. In addition to this existing threat(that will become more sensitive with additional loading), new wind slabs will begin to form on the current snow surface. These slabs will increase in size and sensitivity as the day progresses and are likely to be sensitive in steep terrain by the afternoon.