Avalanche Forecast

Issued: Mar 7th, 2019 3:13PM

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

Alberta Parks michael.olsthoorn, Alberta Parks

Be on the watch for new wind slabs.

Summary

Confidence

High -

Weather Forecast

Friday will be cloudy with light intermittent flurries. Morning temps will be -15c and warming to -10c. Winds will be strong from the West.

Avalanche Summary

One size 2 slab avalanche on a north aspect was observed in the Highwood area.

Snowpack Summary

Wind slabs are in abundance in the Alpine. As you descend to tree line, these slabs seem to quickly disappear, likely due to the persistent facetting. The bridging strength of the midpack that we have been observing all winter at tree line and below has disappeared thus making ski travel challenging, especially if you are making a new track. The wind today has started to move the snow around, so beware of new slabs on the surface.

Problems

Wind Slabs

An icon showing 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.  Be on the watch for new wind slabs with these recent winds.
Caution in lee and cross-loaded terrain near ridge crests.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing 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

Valid until: Mar 8th, 2019 2:00PM