Avalanche Forecast

Issued: Jan 15th, 2014 4:45PM

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

ian jackson, Parks Canada

Banff Yoho Kootenay.

Avalanche control is planned for Mt. Bourgeau and the Vermillion Crossing slide paths. If all the red on the bulletin isn't enough, here is another reason to not go into avalanche terrain tomorrow!

Summary

Weather Forecast

Warm temperatures and clear skies will dominate for the next few days as the surface high moves over us. Winds will be lighter, but still gusty. With freezing levels rising to 1800 m on Thursday and Friday and possibly over 2000 m on Saturday, the big factor to watch for is the warm temperatures, especially on solar aspects.

Snowpack Summary

Strong winds have created widespread windslabs on lee aspects (N-SE) and stripped all the snow off windward aspects. The new snow and wind loading has overloaded the basal weakness and is responsible for the widespread natural avalanche cycle we have been seeing. Although natural activity is tapering, conditions remain prime for human triggering

Avalanche Summary

Avalanche control today on Mt Dennis produced large avalanches up to size 3.5 in areas that had not been previously controlled this season. Additionally, numerous large natural avalanches observed in Kootenay Park and the Lake Louise Backcountry in the last 24h running to the end of historical runouts.

Confidence

Due to the number of field observations

Problems

Deep Persistent Slabs

Full depth avalanches have been seen daily on this layer. We expect another natural avalanche cycle on this layer on sunny aspects with the forecasted warm temperatures and sun.

Stick to non-avalanche terrain or small features with limited consequence.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

2 - 4

Wind Slabs

Any avalanche triggered as a windslab is almost certain to step down to the basal facets and trigger a much larger avalanche.

Good day to make conservative terrain choices.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Jan 16th, 2014 4:00PM