Avalanche Forecast

Issued: Jan 5th, 2017 3:00PM

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

Alberta Parks matt.mueller, Alberta Parks

Good skiing is becoming hard to find. Sheltered areas at treeline are the best bet for decent snow. It is out there...it just takes some searching.

Summary

Confidence

High -

Weather Forecast

Mainly cloudy with isolated flurries tomorrow. Alpine low of -18. Winds will be westerly and up to 20km/hr.

Avalanche Summary

We saw three avalanches today. All in the alpine on east aspects and up to sz 2.5. Interestingly, they were all mid slope and in skiable terrain.

Snowpack Summary

A visit to some of our more remote weather plots today helped to give a more regional perspective on the snowpack. Below treeline is still the same as its been for the last while. Weak snow makes for difficult travel and poor coverage in terms of depth. On the up side, there are very few avalanche concerns! Depths range from 50cm-95cm.Treeline is variable these days for coverage and avalanche problems. Lower treeline suffers from the same weak snow/poor coverage issue. At the upper end of treeline the 10-30cm thick surface windslabs are present in open areas and vary in density. Hardslabs are common in windy areas and don't inspire confidence for ski quality or avalanches. The Dec 18th facet layer is prominent in all areas. It is down 30-50cm with a distinct density change. Lower down, the Nov crust layer is intact and still quite solid as a layer, but we are seeing depth hoar on top of it in most areas now. The alpine is essentially the same as treeline, but more variable. Wind exposure is the thing to keep in mind when predicting the hardslab locations. One common theme was the rapid change from feature to feature. In a few steps, the snowpack character changes considerably.

Problems

Persistent Slabs

An icon showing Persistent Slabs
Activity on this layer indicates it is still easily triggered. There is potential for wide propagations, especially in steep terrain. Use your probe to help find and track the weakness.
If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Choose well supported terrain without convexities.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 3

Wind Slabs

An icon showing Wind Slabs
These vary in thickness and density. Recent reverse loading has put them in unexpected terrain.
Avoid freshly wind loaded features.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
Thin spots will be the likely trigger point. Depth hoar below hardslabs deserves some caution. Also, the surface slabs may step down to this layer.
Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Jan 6th, 2017 2:00PM