Avalanche Forecast

Issued: Mar 3rd, 2012 4:00PM

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

marc ledwidge, Parks Canada

Banff Yoho Kootenay.

Snowfalls and strong winds on the Divide are forecasted to continue for the 24 hours. Widespread natural activity is expected in those areas. This is a good time to pull back the reins until conditions improve.

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

Problems

Persistent Slabs

Snow depths over the Valentines surface hoar and sun crust on steep solar aspects range from 20cm E of the Divide, to 50+cm at Sunshine and Yoho. Continuing snowfalls and strog winds will increase natural activity on this layer.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

2 - 3

Wind Slabs

Moderate winds this week have also created thin, but stiffer wind slab conditions 25-35 cm deep on ridgetop lee terrain. These have been seen to step down to the Valentine layer and are now buried by further snowfalls.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Deep Persistent Slabs

Recent trips east of the Divide have found a shallow, weak snowpack. Tests done showed sudden collapse results on the basal facets. It is still possible to trigger the entire slope from shallow, thinly covered areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Mar 4th, 2012 4:00PM