Avalanche Forecast

Issued: Dec 21st, 2014 4:00PM

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

ian jackson, Parks Canada

Banff Yoho Kootenay.

Some new snow has refreshed the ski quality but also re-hidden many rocks just below the surface. Ride with care in these early season conditions!

Summary

Weather Forecast

Cool temperatures with moderate SW winds and little precipitation on monday. Tuesday afternoon/ overnight we may see 5-15 mm of precipitation and increased SW winds as a system passes over us. This will be short lived with a clearing trend on Wed.

Snowpack Summary

5-10cm's of new snow along the divide has improved ski quality. This new snow has blown around by moderate SW winds to create thin, soft windslabs in the ALP and at TL. These windslabs sit on a surface hoar layer in many areas and will be one to watch in the future. The basal crusts/ facets persist providing a rotten foundation for this new snow.

Avalanche Summary

Cracking of new snow in immediate lees and soft slabs to size 1 reported in the Lake Louise area today.

Confidence

Intensity of incoming weather systems is uncertain on Tuesday

Problems

Deep Persistent Slabs

Natural avalanche activity has subsided but snowpack tests show that the weak facets at the basal level continue to be the big issue. The slab that rests on this weak structure may indicate some strength in places but in fact very little has changed.

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.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Dec 22nd, 2014 4:00PM