Avalanche Forecast

Issued: Dec 12th, 2015 4:00PM

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

Max Darrah, Parks Canada

Jasper.

Enjoy the snow twice as much - carve some turns and dig some pits to look for the Dec3 interface down 60cm.

Summary

Weather Forecast

Snowfall amounts are tapering off, but a series of scattered flurries is expected to bring an additional 10cm by Sunday evening. Temperatures remaining cool, with daytime highs near -5C. Freezing level to remain below 1500m. Winds light and variable through to the weekend.

Snowpack Summary

70 cm of snow in the past week is settling rapidly and appears to be bonding well. The main concern is where this snow sits on the Dec3 surface hoar, most likely between 1700-1900m on sheltered North aspects. A touchy 15cm windslab can be found in lee areas at treeline.

Avalanche Summary

The natural cycle of storm slab avalanches (some stepping down to ground) which occurred following the last big storm has subsided. The majority of the avalanche activity occurred in the alpine and treeline elevation bands. No avalanches have been observed or reported associated with the Dec3 surface hoar layer down 60cm in the Jasper region.

Confidence

Due to the number of field observations

Problems

Wind Slabs

A touchy 15cm windslab can be found in lee areas at treeline and into the alpine. Several natural avalanches started with this slab and then stepped down to full depth releases in the alpine following last weeks storm.

If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Be aware of thin areas that may propogate to deeper instabilites.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Persistent Slabs

Although the Dec3 layer down 60cm has not been associated with any recent avalanche activity, it is still a concern, particularly in sheltered open terrain below treeline. If you find this layer in your travels, please let us know.

Be aware of the potential for avalanches due to buried surface hoar in isolated areas.

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

Elevations: Alpine.

Likelihood

Unlikely

Expected Size

1 - 3

Valid until: Dec 13th, 2015 4:00PM