Avalanche Forecast

Issued: Mar 18th, 2015 4:00PM

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

Lisa Paulson, Parks Canada

Banff Yoho Kootenay.

Winter returns... snow is in the forecast! See the "forecast details" tab for more information on the forecasted weather.

Summary

Weather Forecast

Light flurries move into the region on Thursday and will be accompanied by strong winds.Â Snow is expected Friday-Sunday with up to 10 cm per day expected. Greatest amounts will be along the Continental Divide and West. Winds accompanying the weekend storm will be light SW with moderate gusts.

Snowpack Summary

Recent strong wind has created hard slabs on the snow surface in the alpine. On the Wapta, areas of soft snow with ski penetrations to 15 cm were found today. At and below treeline expect to find a mix of facets and crusts. As ghastly as that combination sounds, generally it is well bonded.

Avalanche Summary

A natural size avalanche size 1.5 was observed near the Balfour Hut on Tuesday. The observer describes the avalanche as a hard windslab. It was noted at 2300m on a North aspect. No other avalanches were observed or reported.

Confidence

Due to the quality of field observations

Problems

Wind Slabs

These wind slabs have become less sensitive, however human triggering is still possible. Likely this will come in the form of a hard wind slab rather than a soft one, if tested.

Use caution in lee areas. Recent wind loading have created wind slabs.The recent snow may now be hiding windslabs that were easily visible before the snow fell.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

The lower half of the snowpack is weak due to the presence of basal facets and depth hoar. This layer has been dormant lately but may be more sensitive with forecasted new snow load, especially in thin areas.

Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Mar 19th, 2015 4:00PM