Avalanche Forecast

Issued: Mar 5th, 2019 3:00PM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

Wednesday could be the first warm day with intense solar radiation. This may lead to an increase in avalanche hazard on solar aspects. Pay attention to localized conditions.

Summary

Confidence

High -

Weather Forecast

Wednesday looks to be another nice day, at least to start. A sunny morning will likely turn to an overcast afternoon with possible very light flurries. Winds will be light from the east, and temperatures will climb to near -7 by the afternoon. Thursday and Friday are expected to be cloudy with very light flurries.

Avalanche Summary

No new natural avalanches were observed today, but helicopter avalanche control work produced several loose and slab avalanches in steeper Alpine terrain up to size 2.0. In general, these slides traveled fairly far due to the loose facets.

Snowpack Summary

Wind slabs can be found in Alpine areas in the the typical places; lee and cross-loaded terrain, gullies, and immediately below ridge-crests. As you descend to Treeline these slabs seem to quickly disappear, likely due to the persistent facetting. Overall the snowpack is very weak and it is possible that loose snow facet avalanches could occur at any elevation, triggered by solar input, cornice failures, loose rocks or a skier/rider. These slides have the potential to run far and could be problematic in gullies and similar terrain traps. At low elevations expect ski penetration to ground if you leave an established track.

Problems

Wind Slabs

A variety of wind slabs can be found through the Alpine. These sit on a layer of facets and could be sensitive to triggering in steeper terrain.

Caution in lee and cross-loaded terrain near ridge crests.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

We are thinking this layer is becoming more reactive over time. As the slabs facet/weaken, the bridging effect will become less reliable. It is also possible that this layer will "wake up" as the days become warmer and the solar input increases.

Be aware of the potential for wide propagations due to the presence of hard windslabs.Be aware of the potential for full depth avalanches due to deeply buried weak layers.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1.5 - 3

Loose Dry

Mostly a problem in steep terrain, but we could start to see some solar triggered slides as well.

Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Mar 6th, 2019 2:00PM