Avalanche Forecast

Issued: Mar 1st, 2018 3:00PM

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 mike.koppang, Alberta Parks

A heavy snowfall warning is in effect but not all of the models are in agreement.  We may see up to 10cm of snow overnight with the majority of this new snow falling in the eastern regions.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Friday

Weather Forecast

We are expecting a weak system to cross over the region tonight and give us a few flurries but not too much in the way of accumulations.  By Sunday we are HOPEFUL that 20cm of new snow will have fallen with very little wind affect.  Temperatures are again supposed to drop back towards -20 by the weekend with light - moderate winds out of the NW.

Avalanche Summary

No new avalanche activity has been observed in the past 24hrs.

Snowpack Summary

This week so far we have only seen 10cm of new snow at the higher elevations.  This snow has been moved around by the NW flow adding load to the previous existing windslabs that had formed across the region.  Forecasters can confirm that wind affected snow is the norm.  Any above treeline terrain has been pummeled by the winds making travel fast but skiing not so appealing.  Cold temps have also facetted out the upper snowpack below treeline making shallow areas very weak.  The midpack is well settled but we are in need of new snow for a bit of a re-set within the snowpack.

Problems

Wind Slabs

An icon showing Wind Slabs
Windslabs are the theme in the alpine and treeline.  Last weeks strong NW flow has created windslabs 10-40cm thick.  Be aware of wide propagation  potential
Use caution in lee areas. Recent wind loading has created wind slabs.Evaluate unsupported slopes critically.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
Large triggers are a concern. It's safe to say we're in the "low probability/high consequence" situation. Avoid thin areas.
Be aware of the potential for full depth avalanches due to deeply buried weak layers.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3.5

Valid until: Mar 2nd, 2018 2:00PM