Avalanche Forecast

Issued: Mar 28th, 2012 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Storm Slabs, Loose Wet and Persistent Slabs.

mike.koppang, Alberta Parks

Kananaskis.

Another system is forecast to push into the area later on Thursday with possibly as much as 20-25cm of new snow. Winds will be in the moderate to strong range so expect rapid slab development and a corresponding rise in avalanche danger.

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain on Friday

Weather Forecast

Avalanche Summary

One Size 2 soft slab on East aspect in Ranger Creek drainage. Ran down to middle of run out zone. Fracture line in start zone appears 60cm, possibly deeper but could not see entire FL. Probable trigger was solar heating effects in rocky terrain above.

Snowpack Summary

Aster Lake region - snow surface moist to 2200m. Smith-Dorrien area - snow surface moist to treeline on solar aspects. Dry snow above with some redistribution by wind occurring.

Problems

Storm Slabs

Storm slabs are present on lee features in alpine areas and wind exposed areas at treeline. These slabs sit on a variety of buried layers including crusts and surface hoar. The bond between the new snow and these layers is variable.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 4

Loose Wet

Daytime heating on sun exposed slopes weakening surface layers. Unreactive while frozen but touchy under influence of full solar effects.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 4

Persistent Slabs

The February surface hoar is buried 120-150cm at treeline. This interface has been strengthening and becoming harder to trigger, but shallow snowpack areas are still a concern. Cornices or smaller avalanches could step down to this layer.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 6

Valid until: Mar 29th, 2012 9:00AM