At the higher elevations new snow and strong southwest to west winds have increased the load on buried layers of crust and in isolated areas faceted snow that formed in October. Slab avalanches are possible on these bed surfaces and could triggered by a person. These slab avalanches are anticipated to be up to two feet deep. Avalanches are unlikely below an elevation of 9,000 feet where snow depths are shallow and old snow layers are not present at the base of the snowpack. Hazards associated with a shallow early season snowpack are also prevalent at all elevations.
On steep shaded aspects above an elevation of 9,000 large slab avalanches are possible on crusts or faceted snow that formed in October. Evaluate the snowpack to determine if these old snow problem layers could produce a dangerous slab avalanche.
( Discussion is generated from the previous day's afternoon forecast. )A winter storm warning has been issued by the National Weather Service. Snow fall amounts of up to 18 inches are possible in the mountains. Strong southwest winds will veer to the northwest during the day as the center of this weather system moves east. Temperatures will be in the teens in the mountains. A significant snow event and strong winds will be rapidly loading leeward aspects and increasing the avalanche hazard. Conditions are expected to become dangerous at the higher elevations on steep avalanche prone slopes where the recent new snow lies upon old October snow surfaces. In those areas, large slab avalanches are possible. These dangerous slides could release naturally or be triggered by a skier or rider. Slabs depths of two to as deep as four feet are anticipated. Conservative terrain choices are warranted. The general avalanche hazard is expected to be considerable at the higher elevations (9,000 to 10,500 feet), moderate at the mid elevations and low below an elevation of 7,500 feet.
