Avalanche Forecast

Issued: Nov 17th, 2017 3:03PM

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

Alberta Parks matt.mueller, Alberta Parks

We've had enough snow recently to increase the coverage and avalanche hazard. How the wind distributes the snow is the big question. Watch closely for windloading as the winds increase.

Summary

Confidence

High -

Weather Forecast

We are expecting snow to come in for Sunday. In the meantime, westerly winds will increase to 55km tonight and tomorrow. Flurries will accompany winds, but amounts won't add up much until Sunday. Temperatures will remain steady at -10°.

Avalanche Summary

Nothing new today.

Snowpack Summary

10-20 cm of new snow came in yesterday and last night. While below treeline areas are improving for coverage, we are still below threshold in terms of avalanche problems. At treeline, the story changes significantly. We have two layers of interest: the "Halloween" crust and recent windslabs. The crust depth varies, but it is generally down 30-40cm from the top. The windslabs sit above the crust and vary in thickness (on average 20-40cm). Tests have had repeatable failures immediately below the crust on a layer facets. As of this afternoon, winds were increasing with windslab development ongoing.

Problems

Wind Slabs

An icon showing Wind Slabs
The winds started to kick in this afternoon. Slabs will build quickly with the amount of available snow. Expect them to reach further down from ridge crests than we have been used to.
Avoid freshly wind loaded features.Be careful with wind loaded pockets while approaching and climbing ice routes.Avoid lee and cross-loaded terrain near ridge crests.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Nov 18th, 2017 2:00PM