Avalanche Forecast

Issued: Dec 6th, 2012 4:05PM

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

snow safety, Parks Canada

Banff Yoho Kootenay.

Wind effect starts above 2400m. Good ski quality reported on sheltered slopes. SH

Summary

Weather Forecast

Only a few cm of snow Friday, with light alpine NW winds and valley bottom freezing levels.Â The weekend looks much the same until Sunday when winds may jump into the strong range again.

Snowpack Summary

Strong SW winds from Tues/Wed. produced wind slabs in exposed alp. and treeline locations. Sunshine backcountry has received approx. 60cm since Dec.1 with lesser amounts in the Lake Louise area. The Nov.6 crust is approximately 20cm above the ground up to approx. 2600m.Â Forecasters on Ferris Glacier (Crowfoot Peak) found 130-180cm on the ice.

Avalanche Summary

Explosive control on Sunshine Road only produced 1 sz.2.5 on Mount Bourgeau (NE asp, 2500m)Â (photo) (francais) which stepped to the Nov 6 crust and was approx.1m deep. Forecasters on Crowfoot peak saw 1 sz.3 & 1 sz.2Â on high NE facing terrain on Vulture Peak which in spots stepped to glacial ice within the last 48-72 hrs.

Confidence

Due to the number and quality of field observations

Problems

Wind Slabs

Natural activity has tapered off, but expect to find windslabs in steep, exposed terrain which climbers and skiers should avoid.

Be careful with wind loaded pockets while approaching and climbing ice routes.Caution in lee and cross-loaded terrain near ridge crests.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 2

Persistent Slabs

Less activity on the widespread Nov.6 crust of late, but explosives produced an avalanche today which failed on this layer above the Sunshine Road. This shows that larger loads are likely required, but if triggered, will cause bigger avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Dec 7th, 2012 4:00PM