Avalanche Forecast
Issued: Nov 30th, 2013 8:22AM
The alpine rating is Storm Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Timing, track, or intensity of incoming weather system is uncertain on Sunday
Weather Forecast
Two weather systems will collide today creating storm conditions over the interior regions. A cold arctic front will interact with moist air from the pacific creating heavy snowfall and moderate to strong winds.Sunday: Heavy snowfall, moderate to strong alpine winds from the SW, freezing levels around 500mMonday: Light snowfall, moderate to strong alpine winds from the NE, temperatures becoming unseasonably coldTuesday: Dry, cold, mostly sunny, moderate alpine winds from the NE
Avalanche Summary
No recent avalanches have been reported but incoming field data is still very limited.
Snowpack Summary
Highly variable snowpack conditions are being reported but typically 1m of old, well-settled snow lies below the new storm snow. New storm slabs are forming on over a variety of old snow surfaces including (1) winds slabs and wind scoured areas in the alpine and exposed areas at treeline, (2) sun crusts on steep south facing slopes, and (3) surface hoar in sheltered areas around treeline elevation and below. There are still two layers of concern within the mid/lower snowpack: the early November surface hoar is down roughly half way (50-60cm) and the October rain crust is near the ground. While these layers have recently become dormant, the weight of the new storm snow may cause these layers to reactivate in isolated areas causing large, destructive avalanches. The October crust can be found in the alpine on north aspects (likely east and west as well). The early November surface hoar appears to be spotty and drainage specific.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 1st, 2013 2:00PM