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

Little Yoho.

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.

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 (Banff region) 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. This kind of observation could be very similar to areas in Little Yoho like the Field ice climbs.

Confidence

Problems

Wind Slabs

Isolated wind slabs are present in the alpine, especially in lee areas. So far reports are that these aren't yet thicker than 20cm, 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 should be come less of a problem as the winds decrease, but climbers especially should monitor wind transport in the alpine. Avalanches haven't been running far but there is lots of 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