Tetons

A persistent weak layer of faceted snow that lies upon a hard October rain crust is a significant problem layer. This layer has been the failure plane and bed surface of multiple avalanche events during the past several days. This layer exists at the base of the snowpack at the upper elevations on east through north to west facing slopes and on steep northerly aspects at the mid elevations. Human triggered slab avalanches are likely and natural slab avalanche activity is possible on this problem layer. These slides will be significantly larger and more widely distributed then they were over the weekend. Cautious route selection and conservative terrain choices are essential. In terrain at the mid and upper elevations where that rain crust is absent density breaks in the storm snow and loose faceted snow at the base of the snowpack warrant assessment as potential instabilities. Avalanches are unlikely at the lower elevations.

Although some snow shower activity and banding continues this phenomenon is on the decrease as a high pressure ridge begins to build in from the west and conditions become dryer. Skies are to remain cloudy overnight and on Tuesday with lingering snow showers. Temperatures will be in the single digits and teens at the higher elevations and in the teens and 20s in the valleys. Winds will be northwesterly at 20 to 25 with gusts to 35 miles per hour and will continue to load on leeward slopes.Dangerous conditions exist at the upper elevations. Poor route selection and/or terrain choices could prove fatal. In steep terrain that is underlain by the facets on rain crust problem layer, large to very large slab avalanches could be triggered by the weight of a single person or release naturally. Remote triggering is a reality and could occur as a result of human presence in an avalanche run out zone. Expert terrain assessment and travel skills are essential for safe travel in avalanche terrain. In isolated areas at the mid elevations this hazard extends down into steep north facing avalanche prone terrain. Storm snow instabilities are a potential concern at the mid and upper elevations in steep terrain where the facet/crust problem layer is absent. Avalanches are unlikely at the lower elevations where the snowpack is still quite shallow. The general avalanche hazard is expected to be CONSIDERABLE at the upper elevations, MODERATE at the mid elevations and LOW at the lower elevations.