Avalanche Forecast

Issued: Dec 21st, 2012 3:00PM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

Be cautious on freshly wind loaded features in the Alpine. Excellent skiing is found in sheltered areas at all elevations.

Summary

Confidence

Good

Weather Forecast

Temperatures in the alpine will be near -12 again on Saturday with winds out of the SW at 50km/h. Light flurries are possible through the day, but snowfall amounts will likely be less than 5cm.

Avalanche Summary

A few loose snow slides have been observed at higher altitudes on steep lee aspects.

Snowpack Summary

10cm new snow overnight with a two day storm total of 20cm. This snow has fallen with very little wind effect at and below treeline. However, in the alpine significant wind slab development has occurred. Cornices are also growing.

Problems

Storm Slabs

Fresh storm slabs have formed in lee and cross loaded terrain in the alpine. Winds are forecasted to remain in the moderate range from the SW which will add to this problem and slabs will become increasingly sensitive to human triggering.

Avoid freshly wind loaded features.>Avoid unsupported slopes.>

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 4

Wind Slabs

Previously formed wind slabs are highly variable in their depth and distribution, but are prominent in alpine areas and isolated locations at treeline. These slabs are now hidden by new snow, so dig down to confirm or deny their existence.

Avoid lee and cross-loaded terrain near ridge crests.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 5

Deep Persistent Slabs

The Nov rain crust is still in the back of our mind. Although field tests are not producing concerning results, shallow snowpack areas are still a possible triggering point for this deep layer.

Be aware of thin areas that may propagate to deeper instabilites.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Dec 22nd, 2012 2:00PM