Avalanche Forecast

Issued: Mar 10th, 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.

Alberta Parks michael.olsthoorn, Alberta Parks

Monday is expected to be sunny and warm.  Avalanche hazard can change quickly with solar radiation.

Summary

Confidence

High -

Weather Forecast

Monday will be a mix of sun and cloud with a high temperature of -4c in the alpine and a freezing level of 2000m. Expect very strong SW winds. Solar radiation will be strong. Looks like some snow developing Tuesday afternoon......Stay tuned.

Avalanche Summary

One new slide observed in Miner's Gully in the Bow Valley.

Snowpack Summary

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.
Caution in lee and cross-loaded terrain near ridge crests.Carefully evaluate terrain features by digging and testing on adjacent, safe slopes.

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

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3

Loose Dry

An icon showing Loose Dry
Solar triggered slides expected, especially on steeper slopes.
Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: East, South East, South, South West, West.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Mar 11th, 2019 2:00PM