Avalanche Forecast

Issued: Dec 6th, 2012 8:28AM

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

burke.duncan, Alberta Parks

Kananaskis.

Avalanche control of the East End of Rundle today - observed rapid propagation across slope. For photos of results see here

Summary

Confidence

Good

Weather Forecast

High pressure pushing into the region from the west with very light precip in the forecast, light to moderate winds and seasonal temps.

Avalanche Summary

Avalanche control on EEOR Thursday produced one Size 3 SSL and 5 Size 2 SSL. Bed surfaces were ground and the November Cr layer. One section of road buried 1-2 M deep X 60M wide.

Snowpack Summary

Limited obs today due to avalanche control efforts. Increased cornice formation noted due to recent winds. Sympathetic cornice release observed during control work.

Problems

Storm Slabs

Strong to extreme winds over previous 48 hours have created widespread storm slabs in alpine areas and isolated wind slabs at treeline. Recent storm snow totals are close to 50cm so lots of snow is currently available for transport.

Be aware of the potential for wide propagations due to the presence of hard windslabs.>Avoid freshly wind loaded features.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 5

Loose Dry

Loose dry avalanches from steep unskiable terrain on all aspects, but more prominent on lee aspects.

Be cautious of sluffing in steep terrain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 4

Persistent Slabs

The Nov rain crust persists about 30+cm off the ground throughout the forecast area and is reactive to stability tests in the hard range. Avalanches in the upper snowpack may step down to this weakness.

Avoid convexities or areas with a thin or variable snowpack.>Avoid runouts where triggering slopes from below is possible.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Dec 7th, 2012 2:00PM