Avalanche Forecast

Issued: Jan 3rd, 2017 4:00PM

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

deryl kelly, Parks Canada

Jasper.

No significant changes expected leading into the weekend.

Summary

Weather Forecast

Extremely cold overnight temps through the forecast area Tuesday night. Warming by mid-day to a reasonable -12. Broken skies and light winds. Some light flurries forecasted for Wednesday afternoon.

Snowpack Summary

Surface snow, alpine pockets and loaded lee features are facetting with the arctic temps and rapidly losing cohesion. Southerly slopes in the alpine have been stripped by previous SW winds and hard slab on lee features. At treeline, the snow is faceted that is barely supportive and weak in shallow areas.

Avalanche Summary

Road Patrol in the Maligne Valley. Loose dry slides up to sz 1.5 out of steep rocky terrain. Slabs up to size 2.5 noted on Mt. Cirrus above and close to the Polar Circus ice climb.

Confidence

The weather pattern is stable

Problems

Loose Dry

Arctic temperatures faceting the surface snow causing it to loose cohesion and release loose dry avalanches in steep alpine rocky terrain. Particularly concerning for ice-climbers in confined terrain.

Use caution above cliffs where small avalanches may have severe consequences.Be very cautious with gully features.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Wind Slabs

Cold temperatures and hard slab conditions make triggering less likely. Triggering from shallow spots remains a possibility.

Caution in lee and cross-loaded terrain near ridge crests.Watch for areas of hard wind slab in steep alpine features.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Persistent Slabs

It is less clear where this layer remains. Shallow areas are weakening and breaking down this layer by faceting with cold temps. Be diligent in your snowpack investigation.

Be cautious in shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1 - 3

Valid until: Jan 4th, 2017 4:00PM