Avalanche Forecast

Issued: Mar 11th, 2012 4:00PM

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

mike.koppang, Alberta Parks

Kananaskis.

A slightly cooler, calmer day on Sunday with some light snowfall through the day and minor amounts expected overnight. Later Monday PM heavy snowfall with up to 30cm expected by Tuesday night to push Danger ratings back to HIGH.

Summary

Confidence

Good

Weather Forecast

Flurries Sunday night tapering off by 0500 Monday AM. Heavy snowfall beginning approx 1700 hours with nearly 30mm of precip carrying over into Tuesday evening.

Avalanche Summary

No new natural avalanche activity observed or reported on Sunday. Skies were somewhat obscured along the divide at midday reducing visibility.

Snowpack Summary

Only a couple centimeters of new snow by Sunday AM Extensive wind affect in the alpine. Freezing level near 2200m on solar exposed slopes today. Snowpack settling rapidly.

Problems

Wind Slabs

Numerous layers of wind slab are prominent on lee and cross loaded features, and favorable 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 - 6

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 - 6

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 12th, 2012 9:00AM