Avalanche Forecast

Issued: Dec 16th, 2014 7:58AM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Persistent Slabs.

ccampbell, Avalanche Canada

South Rockies.

If the riding is good, the snowpack stability might not be.

Summary

Confidence

Fair - Due to the number of field observations

Weather Forecast

A mix of sun and cloud and mainly dry for the forecast period with increasing cloud and a chance of snow by Friday evening. temperatures are expected to gradually increase with daytime highs nearing zero degrees in valley bottoms by Friday. Ridge top winds should remain light but gusty from the southwest.

Avalanche Summary

No new reports of avalanches from the region on Sunday of Monday morning.

Snowpack Summary

Surface hoar is likely growing on a thick hard supportive near-surface rain crust that extends as high as 2100 m, with as much as 15cm of fresh snow on it. Last week's rain and subsequent freezing temperatures has effectively stabilized the snowpack at all but the highest elevations. However, in high alpine areas that did not get rain during the recent storm, there may be a buried persistent weak layer of crust and/or facets that is now down between 70-100 cm. This buried crust from November may continue to be triggered by large additional loads. Pockets of fresh wind slab may also be triggered at or near ridgetops in areas where the snow was dry enough to be transported by the strong Southwest winds during the storm.

Problems

Persistent Slabs

Old facet/crust weaknesses may still be sensitive to triggers on slopes that aren't bridged by a thick surface crust. Generally shady aspects in the high alpine.

Avoid slopes with variable snowpack depths. Avalanches may be triggered from thin spots around boulders or small trees.>Avoid large alpine slopes that have a deeply buried crust with facets. >

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely

Expected Size

2 - 4

Valid until: Dec 17th, 2014 2:00PM