Avalanche Forecast

Issued: Mar 9th, 2019 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 Deep Persistent Slabs.

Alberta Parks jeremy.mackenzie, Alberta Parks

Head's up for fresh wind slabs at higher elevations. Also, keep an eye on the effects of solar radiation. At the moment, it does not look to be a major concern according to the forecast, but if sunny skies prevail, this could change.

Summary

Confidence

High -

Weather Forecast

Possible very light flurries to start the day Sunday should give way to mostly sunny skies and temperatures near -7 at ridge-top. Winds from the SW will pick up in the afternoon.

Avalanche Summary

A few new slides up to size 2.0 occurred in the past 24 hours, with the common denominators being N to E aspects, steep Alpine terrain, with fracture depths between 10 and 40cm. Some small solar triggered sluffs were also observed.

Snowpack Summary

Recent westerly winds have created new surface wind slabs near ridge crests and in alpine bowls on lee and cross-loaded features. These slabs also exist at treeline, but they are not as widespread. The formerly strong midpack has been decimated by a month of cold weather and is now highly variable in its density, with many areas exhibiting no structure at all. Much of the region's snowpack consists of recent wind slabs sitting on up to 80cm of depth hoar and facets. It will be interesting to see how the snowpack adjusts to the recent load and the forecasted warm temperatures. It is likely that full-depth avalanches will become more commonplace in the next few days.

Problems

Wind Slabs

An icon showing Wind Slabs
Variable winds have left us with new wind slabs in the alpine and upper treeline. These slabs sit on a weak layer of facets and will likely be sensitive to triggering in steeper terrain.
Carefully evaluate terrain features by digging and testing on adjacent, safe slopes. 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

An icon showing Deep Persistent Slabs
What will wake up this layer? A skier/rider in a thin shallow snowpack area? Warmer temps with some solar radiation? A cornice failure? This layer deserves respect as any resulting avalanche will be full depth.
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

Valid until: Mar 10th, 2019 3:00PM