Avalanche Forecast

Issued: Dec 13th, 2016 4:00PM

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

snow safety, Parks Canada

Banff Yoho Kootenay.

Back in the deep freeze for the rest of the week. Low danger continues, although the weakening surface snow is resulting in some large sluffs. Strong temperature gradients in the snowpack are weakening it rapidly

Summary

Weather Forecast

More of the same cold, clear weather with little wind. The temperature is expected to plummet to -30C on Friday.

Snowpack Summary

The new, low density snow has done little to enhance snowpack structure. Facetting and depth hoar production are ongoing, especially in thin coverage areas. The November 12th crust is breaking down, with facets being produced on either side of the layer. This persistent weakness is producing moderate to hard results with stubborn characteristics.

Avalanche Summary

No significant slab avalanches have reported or observed in the past week. Loose snow avalanches are occurring out of steeper terrain, mostly related to facetting.

Confidence

The weather pattern is stable on Wednesday

Problems

Loose Dry

The surface snow is faceting rapidly and becoming weak, resulting in large sluffs developing in steep and/or confined terrain. Be very wary of your exposure above and below, and remember to ski off fall line to manage any sluffs growing behind you.

Be aware of party members below you that may be exposed to your sluffs.On steep slopes, pull over periodically or cut into a new line to manage sluffing.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

The Nov 12 crust has weak snow all around it, and is a suspect and dangerous layer. Although it's reactivity seems to have abated during the current cold snap, we expect it to awaken again with additional load and warmer temperatures (one-day).

Avoid shallow snowpack areas where triggering is more likely.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Dec 14th, 2016 4:00PM