Eighteen inches of new snow with around 1.5 inches of moisture has fallen in the mountains since Wednesday afternoon. Moderate to heavy snowfall accompanied by strong westerly winds will continue through the day. At the higher elevations dense slab avalanches could be human triggered or release naturally on slick old snow surfaces and density changes within the new snow. These dangerous avalanches could be un-survivable. Careful snowpack evaluations and a cautious approach to terrain selection will be essential for safe travel in avalanche terrain. Avalanches are unlikely below an elevation of 8,000 feet.
At the higher elevations and on northerly aspects down to an elevation of 8,000 feet dense slab avalanches could be human triggered on old snow surfaces and on density differences within the storm snow. These slabs have been formed by strong west to southwest winds and could be up to 30 inches deep. These slabs will continue to gain depth and volume as the day progresses.
( Discussion is generated from the previous day's afternoon forecast. )A most and rather warm storm system will bring moderate to heavy snowfall to the region and will be accompanied by strong westerly winds. A winter storm warning, issued by the National Weather Service, remains in effect. New snow totals of 1 to 2 feet are expected in the mountains during the next 24 hours. Deeper amounts are possible in the Teton Range. Temperatures will remain in the 20s at the higher elevations. A mix of rain and snow is expected at the lower elevations. West to southwest wind will continue at speeds of 25 to 30 with gusts to 45 miles per hour. The general avalanche hazard is expected to increase to CONSIDERABLE at the upper elevations (9,000 to 10,500 feet). Dense slab avalanches two to four feet in depth could be human triggered or release naturally on slick old snow surfaces. These dangerous avalanches are likely to be un-survivable. Slab avalanches may also fail on density differences within the new snow. At the mid elevations the general avalanche hazard is expected to be MODERATE. Human triggered small to large slab avalanches that fail on old snow surfaces are possible on northerly aspects between the elevations of 8,000 to 9,000 feet. Careful snowpack evaluations and a cautious approach to terrain selection will be essential for safe travel in avalanche terrain at the mid and upper elevations. Avalanches are unlikely below an elevation of 8,000 feet where the general avalanche hazard is expected to be LOW.
