Avalanche Forecast

Issued: Dec 21st, 2011 4:00PM

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.

Landon Shepherd, Parks Canada

Jasper.

Moderate to strong winds continued in the alpine through today but from the north; expect to encounter some reverse loading of south and east facing features at ridgecrests and tree fences.

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

Due to the number and quality of field observations

Problems

Wind Slabs

Windslabs are present in sheltered lee features at Treeline, mostly near ridge tops and protected pockets in the Alpine. The past warm temperatures are helping them bond to older snow surfaces.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Deep Persistent Slabs

Basal facet collapses are still being noted below midpack bridging layers. Shallow snowpack areas and rocky outcrops are likely trigger locations.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Dec 22nd, 2011 4:00PM