At the mid and upper elevations strong winds and increasing snowfall rates are creating dangerous avalanche conditions. These rapid loading conditions could trigger natural avalanche activity on a persistent weak layer. Large slab avalanches are possible on a variety of aspects. Human triggered avalanches are likely and due to the volume of the slabs these slides could have severe consequences. Careful assessment of the snow stability and terrain combined with conservative terrain choices will be essential for safe travel in avalanche terrain. At the lower elevations (below an elevation of 7,500 feet) the snow is shallow and rain soaked.
At the mid and upper elevations a persistent weak layer of faceted snow is being rapidly loaded and is likely to become unstable. Large natural and human triggered avalanches are possible on a variety of aspects with depths from two to four feet. Being caught in one of these dangerous slides could be fatal.
At the mid and upper elevations strong south to west winds are forming new wind slabs on a variety of aspects. These slabs are forming on a variety of old snow surfaces including sun crusts and areas of recently formed surface hoar. These slabs could be human triggered on steep avalanche prone slopes with depths to one foot and have potential to step down several feet to a persistent weak layer and hard crust that formed in late November.
( Discussion is generated from the previous day's afternoon forecast. )A significant increase in the precipitation intensity is expected overnight. Warm air advection will keep overnight temperatures above freezing at the lower elevations. Snowfall amounts at the higher elevations are forecast to be 5 to 10 inches overnight with another 1 to 3 inches possible during the morning hours on Wednesday. Higher amounts in localized areas are possible. Cooler air will begin to move into the region during the day. Winds will be from the southwest tonight and back to the west during the day. Wind speeds are forecasts to be 25 with gusts from 35 to 55 miles per hour.Strong winds will create new soft slabs. The new snow will load our persistent weak layer. If the weather forecast verifies, conditions will become dangerous at the mid and upper elevations. Large natural and human triggered slab avalanches are possible. The persistent slabs will be bigger than they were during the last 10 days as their volume will be comprised of the snow from the previous cycle plus the new snow from this cycle. Careful assessment of the snow stability and terrain will be essential for safe travel in avalanche terrain. The general avalanche hazard is expected to increase to CONSIDERABLE above an elevation of 7.500 feet and be LOW below that elevation.
