Avalanche Forecast

Issued: Mar 2nd, 2012 4:00PM

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

snow safety, Parks Canada

Banff Yoho Kootenay.

Increasing hazard this weekend on the already sensitive Valentines weak layer. Expect increased natural activity as the polar warm front moves in Saturday with strong winds and 10-15 cm of snow. Choose low angled, low consequence terrain. SH

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

Forecast snowfall amounts are uncertain on Sunday

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. New snow and strong winds tomorrow up high (W of divide) 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.

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 3rd, 2012 4:00PM