An avalanche warning remains in effect. Conditions are still very dangerous. Up to 50 inches of snow with 4 inches of moisture has fallen in favored areas since Saturday. Temperatures will be warmer today and did not drop below freezing at the lowest elevations overnight. Very large avalanches could release naturally. Large human triggered avalanches are likely. Very large, destructive avalanches could run full path though mature trees and well out into run out zones. At the lower elevations wet slide activity is likely on a variety of aspects and may become widespread. Roof slides are a serious concern. Travel in avalanche terrain is not recommended.
Dense wind slabs formed by southwest winds exist on a variety of aspects. These slabs could be easily triggered by humans on steep slopes. Natural releases are likely. These slabs could be 3 to 5 feet deep at the mid and upper elevations. They could be up to 2 feet deep at the lower elevations where they could become damp.
Up to four inches of snow water equivalent has been loaded above persistent weak layers of faceted snow in the snowpack. Very large to historic size deep slab avalanche releases are possible on these persistent weak layers. These very dangerous avalanches could run long distances into mature forest, valley floors and flat terrain. These destructive slabs could be up to 6 to 12 feet deep at the highest elevations and 2 to 4 feet deep and wet at the lower elevations.
Skies will be mostly cloudy tonight with scattered light snow showers. Snow will return on Thursday. Expected amounts are 6 to 10 inches in the Tetons, 4 to 8 inches in the Greys River area, and 3 to 5 inches in the valleys. Temperatures will be in the 20s in the mountains and rise into the 30s in the valleys. Winds will be from the southwest at 15 to 25 with gusts to 45 miles per hour. An avalanche warning is in effect until 6 AM on Thursday morning. This avalanche warning will be re-evaluated at 5 AM. Conditions remain very dangerous. Our snowpack has been subjected to a huge multi-day loading event and is struggling to adjust. At the mid and upper elevations dynamic processes are actively occurring in the snowpack (creep and settlement) and are being exasperated by warm temperatures and more snow. All of this is taking place in a snowpack with deeply buried persistent weak layers. Wet slides are a concern at the lower elevations. These conditions present uncertainties with respect to the stability of the snowpack at all elevations. Although the likelihood for large to very large avalanches to release naturally or be triggered by humans may be less that it has been, the consequences of being involved in a large destructive avalanche are severe. For these reasons the general avalanche hazard is expected to be high and travel in avalanche terrain is not recommended.
