Tetons

Weak, faceted snow formed near the ground during dry periods in October and November in terrain above 8000 feet. Avalanches involving this weak snow have been occurring ever since a series of snow storms starting loading it in late November. Conditions remain dangerous. Yesterday a snowboarder triggered a slab avalanche from a remote distance near the Pinedale traverse, south of the Jackson Hole Mountain Resort. These unstable slabs are becoming slightly less sensitive which will make slope evaluation even more difficult. Slopes that were obviously weak and failing upon approach may have gained just enough strength to lure people out onto the starting zones before failing . Caution is advised in all steep avalanche terrain. Avalanches at low elevations are unlikely today.

Wednesday looks to be slightly inverted and mostly clear. Temperatures in the valleys are to be below zero in the early morning while higher elevations bottom out in the single digits. Highs should reach the twenties at all elevations. On summits, Southwest winds are to have ten to twenty mile per hour averages. The general avalanche hazard will continue to be Considerable above 8000 feet in all forecast areas and Low below that elevation. A persistent weak layer of faceted snow lies near the base of the snowpack anywhere that had snow coverage in mid-November. This layer is weak and the chance continues for the presence of a single person to cause a slope to fail and slide. In some areas conditions remain so fragile that such failure could occur remotely, while travelling above or below the avalanche path. In other steep areas, slabs have become less sensitive which is possibly more dangerous as they may not fail until a person is exposed out in the avalanche terrain. Remember that tracks on a slope are not to be considered an indication of stability when dealing with persistent slab problems. Below 8000 feet or in areas not underlain by the old weak snow layers, avalanches are not expected.