Dangerous avalanche conditions exist. Small to large wind slabs could be human triggered on steep avalanche prone slopes. At the upper elevations large, destructive deep slab avalanches with crown depths to five could be triggered by snowmobilers and skiers in steep avalanche paths where a rain crust that formed in October exists at the base of the snowpack. Due to their size, survival is unlikely for a person who triggers a deep persistent slab avalanche. Conservative decisions with respect to terrain and expert route finding skills are essential for safe travel in avalanche terrain.
Strong southwesterly to westerly winds created wind slabs that are one to three feet deep. These slabs could be triggered by snowmobilers or skiers who venture into steep wind loaded avalanche paths.
Deep hard slabs rest upon weak, faceted snow and crusts near the base of the snowpack. These instabilities exist on northwesterly to northeasterly aspects above 9,000 feet. Natural activity on this persistent weak layer occurred as recently as Friday. These dangerous slabs are sensitive to human triggers. With slab depths in excess of five feet, these slides could be fatal.
( Discussion is generated from the previous day's afternoon forecast. )Skies will become mostly clear after midnight and inverted temperatures will develop. Overnight lows in the mountains will be in the negative teens as the valley plummets into the negative mid 20s. Periods of cloud cover and sunshine are expected during the day, and highs will be near zero at all elevations. Northwesterly ridgetop winds will range from 15 to 25 miles per hour.Dangerous avalanche conditions exist above 7,500 feet, and the general avalanche hazard is expected to remain CONSIDERABLE on Sunday. Two avalanche problems will confront backcountry travelers. On a variety of aspects above 7,500 feet, backcountry travelers could trigger recently developed wind slabs up to three feet deep in steep, wind-loaded avalanche terrain. Deep persistent slabs similar to the events that occurred on Thursday and Friday could also be human triggered with fatalities being a likely outcome. While the chance for natural activity for these two problems is decreasing, it might still be possible. Conservative decision making and expert route finding will be essential for safe travel in avalanche terrain.
