Avalanche Forecast
Issued: Feb 7th, 2013 8:01AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
Sylvia Forest,
Parks Canada
Wind slabs in the alpine remain the dominant concern. Cornices have grown large in recent days, and may be the prime trigger for slab avalanches.
Summary
Weather Forecast
A frontal system moving across the interior today will produce light precipitation, while winds ease off. Up to 5cm could accumulate over higher areas. Skies will be mostly overcast with some sunny breaks. A ridge will move in on Friday, bringing drier conditions and a bit more sun.
Snowpack Summary
Soft and hard slabs have formed in the alpine and treeline, mostly on lee aspects (N and E), from wind transported storm snow. On solar aspects, these slabs overly a sun crust (formed on Feb. 3rd) and overlies firm old snow elsewhere. The mid-pack is generally strong, but has become weaker in shallow areas and around trees and rocks.
Avalanche Summary
Avalanche control operations in the park yesterday produced 30+ avalanches on all aspects. Most of these involved surface soft slabs, running to end path or the top of the fans. Two larger avalanches ran to the highway. There were no recent reports of avalanches in the back country, and permit areas were closed yesterday for control work.
Confidence
Due to the number of field observations
Problems
Wind Slabs
Winds tapered off overnight, but the slabs that formed previously remain a concern. Expect pockets of slab in lee features and near ridge crests. Slabs will be thicker on lee aspects, but persist on solar (S + W) aspects over the Feb. 3 sun crust.
Be cautious as you transition into wind affected terrain.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 8th, 2013 8:00AM
