Avalanche Forecast

Issued: Mar 10th, 2012 3:00PM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

Avalanche danger will rise during sunny and warm periods on Sunday. Solar triggered avalanches up to size 2 occurred today. Buried surface hoar and recent wind slabs remain very sensitive to human triggering. Choose conservative terrain.

Summary

Confidence

Fair - Freezing levels are uncertain

Weather Forecast

Light flurries and warm temperatures for Sunday. Winds expected to be moderate to strong from the SW.

Avalanche Summary

A few solar triggered slides up to size 2.0 were observed on SE, S and SW aspects.

Snowpack Summary

Highly variable new snow amounts overnight ranging from 5 to 25cm at treeline. Extensive wind affect in the alpine. Moist snow on solar aspects by midday and above freezing temperatures affected the snow up to at least 2000m on all aspects. Snowpack settling rapidly. Snow stability was deteriorating with radiation and warming at and below treeline.

Problems

Wind Slabs

Numerous layers of wind slab are prominent on lee and cross loaded features, and favourable weather conditions exist for continued slab formation. A failure in these slabs will likely step down to the surface hoar or the basal facets.

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 7

Persistent Slabs

Surface hoar buried up to 100cm 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. Several recent avalanches have stepped down to this layer.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - 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

Expected Size

2 - 6

Valid until: Mar 11th, 2012 9:00AM