Avalanche Forecast

Issued: Dec 24th, 2012 4:00PM

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

garth lemke, Parks Canada

Jasper.

Happy holidays.

Summary

Weather Forecast

Temperature inversion will continue. Weather not expected to change next few days. Expect mainly sunny, perhaps some very light flurries, and light yet cold North winds.

Snowpack Summary

Thursday's 10 cm and another 8cm on Sunday has buried previous wind slabs at tree line and above. The mid-pack remains supportive however expect it to be loosing strength in shallow locations as facetting process continues.

Avalanche Summary

Friday's avalanche control work at the Icefields released several loose size 2 avalanches in thin steep snowpack areas below treeline. Natural avalanches have been limited to similar characteristics, steep, rocky, thin areas creating loose avalanches.

Confidence

The weather pattern is stable

Problems

Wind Slabs

Thursday's 10 cm and Sunday's 8cm of snow with little wind has buried the preexisting wind slabs. Winds have shifted from S to N yet remain in light range. Watch for reverse loading patterns from local terrain influences.

The recent snow may now be hiding windslabs that were easily visible before the snow fell.Caution in lee and cross-loaded terrain near ridge crests.

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

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Deep Persistent Slabs

The strong mid-pack above this weakness is slowly loosing its strength. Shallow snow pack areas are potential trigger spots. Consequences would be severe if initiated.

Carefully evaluate and use caution around thin snowpack areas.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely

Expected Size

2 - 4

Valid until: Dec 25th, 2012 4:00PM