Avalanche Forecast

Issued: Jan 23rd, 2016 3:00PM

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

matt.mueller, Alberta Parks

Kananaskis.

The current windslab will likely stabilize in the next few days, but the January 6th facet layer will linger. The current snowpack is relatively complex, and deserves a fresh perspective on what is reasonable.

Summary

Confidence

High

Weather Forecast

Mainly cloudy with isolated flurries. There may be a few cm's of accumulation from these flurries. Expect an alpine high of -6. Winds will be up to 35km/hr and from the NW. Freezing level will be around 1500m.

Avalanche Summary

Forecasters ski cut a sz1 windslab today on a 38 degree, south aspect moraine (known as Mt. Murray Moraines). The avalanche was 10-30cm thick and traveled about 50m. Traditionally, this moraine does not perform with ski cuts so it suggests that windloading is a problem right now.

Snowpack Summary

Below treeline the current snowpack consists of a thin crust on top, followed by a weak layer of facets that go to the ground. In some deeper areas the snowpack still carries well, but trail breaking is generally about 30cm deep with the odd section of wallowing. There was some new snow last night, but only a few cm's. At treeline, where the snow is deeper (115cm on average)Â still carries well and has some support. The melt/freeze crust goes up to 205-m. At the upper elevations, or areas that are wind prone, expect windslabs. The Jan 6th facet interface is the one to look for and it is down 20-30cm's. The alpine currently has windslabs in any lee area, as well as a persistent weak layer (Jan 6th). The depth of the Jan 6th layer varies greatly, generally 20-40cm down. So far the windslabs tend to be in immediate lees, but approach any windloaded feature with caution as there is a great deal of variability out there right now.

Problems

Wind Slabs

Scoured areas are the obvious indicator for this problem. Immediate lee and cross loaded areas are suspect at the moment. Watch for increasingly "cakey" snow as you approach ridges and open areas.

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

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Persistent Slabs

Thin areas are back on the radar as likely trigger points for this layer. It feels like this layer could sneak up on you and be a big surprise. Continually assess this layer as you travel.

Dig down to find and test weak layers before committing to a line.>Avoid shallow snowpack areas where triggering is more likely.>Avoid steep lee and cross-loaded features>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Valid until: Jan 24th, 2016 2:00PM