Avalanche Forecast

Issued: Apr 21st, 2013 4:00PM

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

Snow Safety, Parks Canada

Banff Yoho Kootenay.

Good spring conditions exist. Recent storm snow has created wind slabs in open areas above treeline. Solar effect will become more of a concern throughout the week. JBW

Summary

Weather Forecast

Cool north westerly flow will prevail until Wednesday as a ridge becomes anchored off the coast. Unsettled conditions will bring convective flurries. The ridge builds inland for a significant warm up by Wednesday-Thursday.

Snowpack Summary

Cooler conditions should keep the crust solid for much of the day. Recent snow has created wind slabs just below ridge crests up to 30-40 cm thick. These slabs have been more touchy on southerly aspects where they overly a crust, but could be triggered on northerly aspects as well. Solar effect will loosen up the recent new snow on steeper terrain.

Avalanche Summary

Several small skier triggered windslabs up to size 1.5Â have been reported over the last few days. These have been triggered on steep terrain just below ridgecrests. Storm snow over crust is the main ingredient.

Confidence

Problems

Wind Slabs

Moderate winds have created areas of thin wind slabs in open areas above 2200 m. These slabs were more sensitive to triggering on southerly aspects where they overlie a smooth crust, but sare also a concern on northerly aspects.

Avoid freshly wind loaded features.Stay off recent wind loaded areas until the slope has had a chance to stabilize.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Apr 22nd, 2013 4:00PM