Avalanche Forecast

Issued: Mar 2nd, 2012 3:00PM

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.

Field day today in the Tent RIdge area. Buried surface hoar layer at treeline quite reactive in tests. Still some cracking and minor whumpfing observed in open areas. Light snowfall and winds increasing as the day went on. / BD

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain on Sunday

Weather Forecast

Warm polar front supported by some moist air crossing region producing milder temps and some light snow flurries. NW winds expected to increase.

Avalanche Summary

No new observations on Friday due to obscured skies in afternoon.

Snowpack Summary

Trace amount Hn overnight. Mix of HSL and SSL in ALP. 120213 SH still reactive to stability tests now down 30 to 70cm. Compression test results in easy to moderate range at TL site (2300m)

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 Thursday 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 Thursday 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 ridge crests.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 6

Valid until: Mar 3rd, 2012 8:00AM