At the mid and upper elevations, backcountry travelers could trigger pockets of persistent slab in steep, avalanche prone terrain. Very little snow exists at the lower elevations and avalanches are unlikely. Evaluate the snow and terrain carefully and identify features of concern, such as recently wind loaded slopes.
Persistent slabs, one to two feet in depth, lie upon a firm crust formed in October. A persistent weak layer of surface hoar developed on this crust prior to being buried. Backcountry travelers venturing into steep avalanche terrain where the October crust is present (primarily upper elevation, northerly slopes) could trigger these slabs, particularly on recently wind loaded leeward slopes.
The mild conditions we have been experiencing are expected to continue until a cold front moves across the area on Wednesday night. On Tuesday skies will be mostly cloudy. Scattered snow shower activity will be limited to the higher elevations. Temperatures will rise into the low to mid 30s in the mountains and into the 40s in the valleys. Winds will southwest at 15 to 25 miles per hour at 10,500 feet.The general avalanche hazard is expected to be MODERATE at the upper elevations and LOW at the mid and lower elevations. At the upper elevations areas of unstable snow persist, especially on steep northerly aspects. Dense slabs one to two feet in depth lie upon a persistent weak layer and could be triggered on steep avalanche prone slopes. Warm temperatures will increase the sensitivity of these slabs to human triggers.Grand Targhee Resort will be preparing its slopes for a Friday opening and will be closed to uphill traffic on Tuesday, Wednesday and Thursday.
