Avalanche Forecast

Issued: Dec 21st, 2018 3:00PM

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

mike.koppang, Alberta Parks

Kananaskis.

The snowpack will be slow to stabilize with the cooler temps forecast. Cracking and whumpfing is still common at treeline so mellow terrain is key!!

Summary

Confidence

High.

Weather Forecast

The long story short is temperatures are gonna get cooler, the skies will begin to clear and winds will decrease out of the NW as a cooler air mass moves into the region. No significant precip is expected for the next few days.

Avalanche Summary

A few new size two avalanches were observed mainly at the treeline. Slab depths looked to be around 100cm with propogations of up to 50m. The Smuts Fist Col also failed in the storm sz 3 likely running full path. More slides also likely occurred but fracture lines were filling in quickly due to new snow and winds.

Snowpack Summary

Another 10cm of snow over the past 24hrs brings our total amounts of settled storm snow up to 60-70cm. This new snow is overlying the dec 10th facet interface the is producing easy to moderate shears down 60ish cm. This layer may be deeper in more wide affected areas and also more reactive. Forecasters on Friday turned around at a treeline feature due to whumpfing and cracking on this interface. With the snowpack doubling in the past week it is overloaded and primed for human triggerred avalanches. Pull back and stick to conservative terrain with minimal overhead exposure.

Problems

Persistent Slabs

Forecasters are still experiencing whumpfs and cracking on the Dec 10th interface down 60-70cm at treeline.

Avoid areas with overhead hazard.Use conservative route selection, choose moderate angled and supported terrain with low consequence.Avoid freshly wind loaded features.

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

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2.5

Deep Persistent Slabs

While the crusts at the base of the snowpack have not produced an avalanche for some time, they are still very much in our mind as a potential layer for other slides to step down to.

Be cautious in shallow snowpack areas where triggering is more likely.Be aware of the potential for full depth avalanches due to weak layers at the base of the snowpack.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3

Valid until: Dec 22nd, 2018 2:00PM