Avalanche Forecast

Issued: Dec 16th, 2018 3:00PM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

Human triggering is likely. This is not the time to be stepping out into big terrain.

Summary

Confidence

High -

Weather Forecast

Monday will bring trace amounts of snowfall with continued strong to extreme westerly winds. Alpine temperatures should reach a high of -6. Tuesday will stay windy and there is some potential for 10 to 15cm by end of day Wednesday.

Avalanche Summary

Avalanches up to size 2.5 were observed in Treeline and Alpine terrain over the last 48 hours. Natural avalanche activity is tapering off, but human triggering is still prime.

Snowpack Summary

Another 2cm of fresh snow overnight brings the recent storm snow up to 40cm at Treeline. Widespread wind slabs have developed and we have seen lots of cracking, reports of whumpfing, and skier controlled avalanches on the Dec 10th surface hoar and facet interface down 40-50cm. Recent natural avalanche have stepped down to the Oct crust with fracture depths over 1m.

Problems

Wind Slabs

Wind slabs are in the human-triggerable range with failures down 30 to 50cm.

Avoid freshly wind loaded features.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Deep Persistent Slabs

There are a number of weak facet layers lurking deep in the snowpack. Be sure to dig and assess before jumping into ski terrain. Even pieces of small terrain could kick out a decent size avalanche.

Avoid unsupported slopes.Dig down to find and test weak layers before committing to a line.Be cautious in shallow snowpack areas where triggering is more likely.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 3

Valid until: Dec 17th, 2018 2:00PM