Avalanche Forecast

Issued: Dec 23rd, 2017 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 Loose Dry.

stephen holeczi, Parks Canada

Banff Yoho Kootenay.

Alpine danger will be dictated by the amount of wind transport Sunday. Lots of low density snow to blow around. It looks to be another cold and sunny day. SH

Summary

Weather Forecast

The arctic air continues Sunday through the first part of next week. Lows will be in the -20's with decreasing alpine NW winds and sunny skies.

Snowpack Summary

15-30cm of recent storm snow with some alpine wind effect sits over the Dec.15 layer. This weak layer consists of surface hoar (at tree-line and below), sun crust or facets (depending on location). Mod shears have been observed on this interface.

Avalanche Summary

A loose dry size 1.5 was observed on Rogan's Gully today. A piece of fresh cornice broke off from wind loading and triggered the slide. It did not go over the climb. No other natural activity was noted.

Confidence

Problems

Wind Slabs

Wind slabs are present in the alpine, especially in lee areas. So far reports have found these to only about 20cm thick, but pay attention to local winds as conditions can change quickly if they pick up.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Loose Dry

This problem should decrease as the winds die down, but climbers especially should watch wind transport above their climbs in alpine terrain. There is still lots of available snow for transport.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 24th, 2017 4:00PM