Avalanche Forecast

Issued: Jan 8th, 2018 4:00PM

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

aaron beardmore, Parks Canada

Banff Yoho Kootenay.

Small amounts of new snow are slowly accumulating adding load to the Dec 15th layer. Forecasters are uncertain as to exactly when the scales will tip in the direction of increased avalanche hazard. Likely, we will see an increase Weds.

Summary

Weather Forecast

The forecast calls for up to 20cm of new snow by the end of Wednesday. Temperatures are also expected to drop into the -15 range by Thursday, with cloudy skies throughout. Wind is expected to increase in to the moderate range throughout Tuesday from the SW.

Snowpack Summary

30-50cm of snow sits over the Dec 15 layer of surface hoar or sun crust, and is developing soft slab properties with the warmer temps wind and approx 10cm of new snow. Below this the snowpack is heavily faceted with remnants of older crust's still lingering throughout. Concern remains in steep faceted gully's where loose dry avalanches can occur.

Avalanche Summary

Lake Louise ski area reported that patrollers could ski cut size 1 loose dry avalanches in very steep and confined terrain. Otherwise nothing observed or reported.

Confidence

Forecast snowfall amounts are uncertain on Tuesday

Problems

Wind Slabs

Recent snow is being moved around by the SW winds and forming thin wind slabs in immediate lee areas. These slabs can fail on the either the weak facets or the Dec 15 layer, and have been triggered by climbers and skiers in the last few days.

Watch for surface cracking and stiffer surface layers of snow. Avoid wind loaded terrain.Use caution in lee areas. Recent wind loading has created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Loose Dry

Loose dry surface snow avalanches will continue to be a problem in steep rocky areas and gullies until the facets round out and begin to bond better. Additionally, we have small amounts of new low density snow adding to the problem.

On steep slopes, pull over periodically or cut into a new line to manage sluffing.The volume of sluffing could knock you over; choose your climb carefully and belay when exposed.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Jan 9th, 2018 4:00PM