Avalanche Forecast

Issued: Mar 16th, 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.

ian jackson, Parks Canada

Banff Yoho Kootenay.

Last nights up-slope storm dropped up to 20cm on the southern and eastern areas of the forecast region with little to no wind. Great skiing to be had, but watch for hidden rocks and give any older windslabs some time to settle.

Summary

Weather Forecast

We are under the influence of a ridge of high pressure until Friday. Tuesday will be a great day to be in the mountains with light winds, sunny skies and a good freeze. Wednesday and Thursday will have weaker freezes and potentially cloudier skies, but light winds and no precip.

Snowpack Summary

5 - 20 cm's of new snow with light E winds from last night overlies a variety of old surfaces. Northern and western areas received less snow than Southern and Eastern areas. This new snow overlies isolated windslabs in the alpine and at treeline from Saturday PM's warm/ windy storm. Below 1900m, surface crusts exist as long as temps stay cool.

Avalanche Summary

Some small wind slabs reacting to ski cuts and explosives but nothing larger than size 1.5.

Confidence

The weather pattern is stable

Problems

Wind Slabs

Moderate to strong SW winds on Saturday evening created wind slabs that will be most touchy where they overly suncrusts.

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 the new 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 17th, 2015 4:00PM