Avalanche Forecast

Issued: Mar 6th, 2014 4:00PM

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

stephen holeczi, Parks Canada

Banff Yoho Kootenay.

Nice powder skiing to be had, just stick to conservative terrain with little overhead hazard. We will be conducting avalanche control on Mt. Bourgeau on Friday, no outdoor activities there during that time. SH

Summary

Weather Forecast

Light snow accumulations expected for Friday with W winds light gusting moderate and temperatures in the alpine will be in the -5 to -10C range. The weekend forecast currently is for strong westerly winds Friday night and Saturday with another 10-20cm (less amounts in the Banff region) possible by the end of the weekend.

Snowpack Summary

Sunshine, Kootenay and Yoho areas have received up to 60cm of storm snow since March 2. Lesser amounts of 25-30cm around Lake Louise and Bow Summit. 40-100cm on the Feb 10 interface of facets,surface hoar,suncrust is producing moderate to hard, sudden planar results. Fresh wind slabs up to 40-60 cm deep in the alpine are reactive to skier control.

Avalanche Summary

We had limited visibility today. Two significant skier triggered avalanches (Class 2 and 2.5) reported at 1700 m (east aspect) in Kootenay yesterday. These initiated 50-100 cm down on the Feb 10 interface and propagated up to 100 m. Less avalanche activity has been observed in the Louise group over the last few days.

Confidence

Due to the number and quality of field observations on Thursday

Problems

Persistent Slabs

Test results on the Feb10 layer mainly in the moderate range with potential for wide propagations if triggered. The recent snow has been shown to overload this layer in the Kootenay,Sunshine, Yoho areas, and less so in the Louise region and Hwy. 93N.

Dig down to find and test weak layers before committing to a line.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Wind Slabs

Lots of recent snow and moderate westerly winds have created touchy wind slabs 40-60cm thick in many wind exposed areas.

The new snow will require several days to settle and stabilize.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Mar 7th, 2014 4:00PM