Avalanche Forecast

Issued: Mar 1st, 2012 8:44AM

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

mike.koppang, Alberta Parks

Kananaskis.

Tricky conditions remain. Buried surface hoar is still reactive. Snowboarders triggered a size 3.0 avalanche today on Tent Ridge. The initial wind slab was 25cm deep, but the slide stepped down to the ground. Luckily everyone is OK.

Summary

Confidence

Good

Weather Forecast

Light flurries with strong NW winds and cool temperatures.

Avalanche Summary

Tent Bowl size 2.5 Na last 24 to 48hrs. Sa size 3.0 today in adjacent gully to Tent Bowl, E asp, 2500m. Snowboarder entered slope from top and immediately triggered a 25cm deep slab that flowed 1/3 path and then stepped down to basal FC/DH. No involvement. One size 2.0 on Hero's Knob, Na, 2300m, ran full path, suspect 120213 SH.

Snowpack Summary

Trace amount Hn overnight. SSL in ALP. 120213 SH still reactive to stability tests now down 30 to 70cm.

Problems

Persistent Slabs

The Valentine's surface hoar and sun crust continue to be problems with extensive avalanche activity in the past week. The surface hoar is particularly touchy and is buried 30 to 70cm. Remote triggering, cracking and whumpfing are occurring.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 6

Wind Slabs

Widespread wind slabs in the alpine on lee and cross loaded features. It is likely that a failure in these wind slabs will step down and trigger the buried surface hoar. A party triggered a slide on this layer today which stepped down to ground.

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

1 - 6

Deep Persistent Slabs

Weak facets and depth hoar linger at the base of the snowpack. Thin steep areas are the most likely trigger points. Snowboarders triggered a size 3.0 slide on this layer when the initial wind slab stepped down to ground.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Cornices

Cornices have grown significantly in the alpine. Failures continue to occur and have triggered avalanches up to size 2.5 on the underlying slopes. Give cornices a wide berth and stay well back from corniced ridgcrests.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 6

Valid until: Mar 2nd, 2012 8:00AM