Avalanche Forecast
Issued: Dec 16th, 2013 8:23AM
The alpine rating is Storm Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Due to the number and quality of field observations
Weather Forecast
Tuesday: Another large storm hits the Northwest with heavy precipitation and strong southwest winds. Freezing levels may spike again as the storm passes through.Wednesday: Pacific frontal system exits the area and moves off to the east. Freezing levels drop to valley bottom for most of the forecast area through the next few days as arctic air moves south.Thursday: Freezing levels remain at valley bottom as the arctic air pushes south between storms.
Avalanche Summary
Numerous size 2-3 avalanches have been observed in the bear pass area. These mainly occurred on north through east slopes that are lee to strong southwest winds.The warm new snow is likely not bonding well to the weak layers formed in early December. Heightened avalanche activity and conditions will continue through Tuesday. Lower elevations are experiencing moist or wet natural avalanches releasing at or near the ground. This will become less of a problem once the freezing levels start descending back down to valley bottoms. Lee slopes will be touchy at upper elevations until this storm snow gets a chance to bond.
Snowpack Summary
Heavy wet snow has fallen at upper elevations with freezing levels rising to 1500m during the last storm. Strong Southwest winds have transported the new snow creating storm slabs that sit above a weak layer formed during the last cold snap. Surface hoar, and facets in the upper snowpack are now buried anywhere from 50 to 80cm from the surface by the recent storms.Earlier in the week, reports from the Shames area at 950m elevation suggested the mid and lower snowpack was composed of various faceted layers and a stiff 4 cm crust. Another crust can be found closer to the base of the snowpack. The recent precipitation will strengthen the snowpack at lower elevations, but may prove to be problematic with rapid wind loading at upper levels.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 17th, 2013 2:00PM