Avalanche Forecast

Issued: Dec 25th, 2013 4:00PM

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

max darrah, Parks Canada

Jasper.

A shallow snowpack, deep persistent slab and basal weakness have created a tricky start to the season - conservative route selection and avoidance of big terrain in the alpine is advised. Have a safe and happy holiday season!

Summary

Weather Forecast

Mild temperatures with minimal precipitation expected over the next few days.Â Winds to remain light to moderate from the SW.Â Freezing level around 1000m.

Snowpack Summary

Variable snow distribution at treeline and above. Wind slabs continue to develop in lee terrain features. Wind slab buried by recent light snow overlies a facetted snowpack and multiple early season crusts. The crusts are distributed unevenly in the forecast area. Facets and depth hoar are just off the ground. This weak base will persist longterm.

Avalanche Summary

Sunday observed several size 2's, likely solar initiated, on cross-loaded gullies above the weeping wall on Mt. Cirrus. They stopped mid-path. Saturday, we observed 2 size 3 avalanches on east facing cross-loaded alpine bowl near Mt. Saskatchewan/Wilson area, 2 size 2.5 on a similar aspect in the Winston Churchill range.

Confidence

Problems

Deep Persistent Slabs

Variable distribution of a persistent slab near the bottom of a shallow snowpack. Although stubborn, if this slab is triggered it will result in a full depth avalanche running on weak layers at or near the bottom of the snowpack.

Be aware of the potential for full depth avalanches due to deeply buried weak layers.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Wind Slabs

Winds continue to be primarily from the Southwest and will likely form new pockets of windslab in exposed areas above treeline.

Be careful with wind loaded pockets. Be aware of wide variation in snowpack depth

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Dec 26th, 2013 4:00PM