Avalanche Forecast

Issued: Mar 13th, 2012 4:00PM

The alpine rating is high, the treeline rating is high, and the below treeline rating is high. Known problems include Storm Slabs, Persistent Slabs, Deep Persistent Slabs and Cornices.

jeremy.mackenzie, Alberta Parks

Kananaskis.

40cm of storm snow already at treeline and more to come. Strong SW winds will continue pushing the danger level firmly into HIGH. Travel in avalanche terrain is not recommended.

Summary

Confidence

Good

Weather Forecast

Continued light to moderate snowfall with strong to extreme SW winds on Wednesday. Another significant wave of precipitation expected to begin on Wednesday night with 40 to 50cm of snow possible.

Avalanche Summary

Visibility was extremely poor today, so observations are limited. Ski cutting was producing medium size sluffs in steep terrain below treeline.

Snowpack Summary

25cm of new snow overnight brings storm snow totals to near 35cm at treeline. The storm snow sluffs easily in steep terrain with ski cutting. Fresh wind slabs are forming at treeline and alpine elevations.

Problems

Storm Slabs

With continued snowfall and winds, wind slabs will continue to build at treeline and above in lee and cross loaded terrain. These slabs are very touchy and will be highly susceptible to human triggering for a couple of days. Choose low angle terrain.

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 6

Persistent Slabs

Surface hoar buried up to 130cm continues to be a major concern in the snowpack. A dense slab now sits on top of this layer. Remote triggering is a real possibility. Many avalanches have stepped down to this layer.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 7

Deep Persistent Slabs

The weak basal facets and depth hoar have re-awakened. Large terrain features are areas of concern where a smaller slide could step down and trigger a very large avalanche with deep and wide propagation.

Aspects: North, North East, East, South East.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

3 - 8

Cornices

Cornices have grown significantly in the alpine. Failures continue to occur and have triggered avalanches up to size 3 on the underlying slopes. Give cornices a wide berth and stay well back from corniced ridge crests.

Aspects: North, North East, East, South East.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

2 - 7

Valid until: Mar 14th, 2012 9:00AM