Avalanche Forecast

Issued: Mar 16th, 2014 4:00PM

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

aaron beardmore, Parks Canada

Banff Yoho Kootenay.

Although the storm is easing off, avalanches are still ripe for human triggering. Sticking to simple terrain is wise until things settle down.

Summary

Weather Forecast

The storm is already starting to taper off. However, given the recent new snow load, the danger rating will remain high. Expect little in the way of precip until Wednesday. Additionally temps will drop slightly and winds will die down. Overall the weather inputs over the next week will do little to improve the danger rating dramatically.

Snowpack Summary

The Lake Louise area received 35cm + of storm snow overnight, less in the Sunshine area (17cm). The new snow now puts the Feb.10th layer is down 80-140cm and is still showing easy to moderate test results in thinner snowpack areas, and harder results in deeper snowpack areas. Areas with buried sun crust are especially touchy.

Avalanche Summary

Parks Canada responded to a skier accidental size 3 yesterday with involvement. One person was fully buried and dug out by his companions in approx 15min. The subject was critically injured. It occurred on Helen Shoulder on a SW aspect in a large avalanche path facing 93N. Today, evidence of a widespread cycle up to size 3 was noted in Yoho.

Confidence

Intensity of incoming weather systems is uncertain on Wednesday

Problems

Persistent Slabs

As yesterdays avalanche indicates, the basal weaknesses are still susceptible to human triggering. Use caution in steep, shallow areas that have not previously avalanched.

Avoid areas with overhead hazard.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 4

Storm Slabs

Although the new storm slabs are unlikely to produce very large avalanches they are still quite touchy.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 3

Wind Slabs

Closely associated to the new storm slabs, wind-slabs will be located at higher elevations in direct lee areas. Because of wind transport the wind slabs will be thicker (up to 40cm) than the storm slabs and potentially more touchy.

Use caution in lee areas. Recent wind loading have created wind slabs.If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 2

Valid until: Mar 17th, 2014 4:00PM