Avalanche Forecast

Issued: Dec 5th, 2011 9:01AM

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

Avalanche Canada ghelgeson, Avalanche Canada

Summary

Confidence

Fair - Due to limited field observations

Weather Forecast

A weak inversion builds into the area Monday evening persisting through the bulk of the day Tuesday. A cold front moves through the region Tuesday bringing light precipitation & a breakdown of the inversion. Winds bump up to 40 - 55 km/h out of the west Tuesday night with frontal passage. Freezing levels remain near valley bottom Wednesday, gradually rising to 1500m on Thursday. A stationary ridge of high pressure persists through the foreseeable future keeping the region dry.

Avalanche Summary

No new avalanche activity has been reported. If you have any avalanche observations to report, please email us at: forecaster@avalanche.ca.

Snowpack Summary

There have been a few observations of a SH layer buried just beneath the snow surface. This SH layer is 3-6mm in size and is buried 1-4cm down. It could still get wiped out with the right winds or temperatures, but, it's worth keeping in the back of our minds. With continued high pressure and low temps forecasted mid-week, conditions will once again be primed for SH development. At this time, it would be a good exercise to get out and see if you've got surface hoar below the snow surface in your favorite riding areas. A rain crust is present just below the snow surface below 1800m which is something we'll need to watch. The main concern at the moment are lingering wind slabs, but, I suspect they're losing energy by the day.My guess is that the good riding with quality pow turns will be in sheltered locations that were not exposed to wind. Generally there is about 150-200cm in the alpine. Treeline depths are between 50 -150cms. Recent snow pack observations are indicating the late October rain crust is present in the alpine elevations and down approximately 120cm. This crust is said to be up to 5mm in thickness with predominate faceting below it. For the moment the crust seems to be bridging over the facets below, with a well settled 1F - P midpack above.

Problems

Wind Slabs

An icon showing Wind Slabs
Due to shifting winds, wind slabs may be found on all aspects. If a weakness exists lower in the snowpack, a wind slab release may step down deeper producing larger avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 4

Valid until: Dec 6th, 2011 8:00AM