Avalanche Forecast

Issued: Jan 10th, 2017 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 Deep Persistent Slabs.

grant statham, Parks Canada

Banff Yoho Kootenay.

We switched our problems today to a Deep Persistent Slab, and a Wind Slab. The DPS problem is here for the long run, due to the weak faceted base. The WS problem is more dynamic; coming & going more often. Right now the N wind has created hard slabs.

Summary

Weather Forecast

Clear and cold for the next few days, with gradual warming starting for the weekend. Wednesday's temperatures will range from -16 to -25, with light winds out of the north (moderate winds up high). With the wind, the temperatures are brutal right now so be sure to bring tonnes of extra warm clothing and take care to not let yourself get too cold.

Snowpack Summary

18 cm of snow from the past 48-hr has been blown to smithereens by northern winds at treeline and above. This has produced a reverse loading pattern, with hard slabs in many starting zone areas overlying a weak, faceted snowpack with numerous instabilities in the lower half of the snowpack. This is today's snow profile from Bow Summit.

Avalanche Summary

SIze 1 skier accidental avalanche in a wind loaded gully at Bow Summit today, followed by our team getting a significant crack in the adjacent gully. Observed a size 2 natural avalanche in a leeward (from the north wind) feature on Observation Peak also. Lake Louise ski hill reported several hard to trigger slabs up to size 1, and lots of cracking.

Confidence

Problems

Wind Slabs

Winds from the north have created hard wind slabs in many areas, and these are reverse from normal locations. These slabs are hard to trigger, with a single person, but if they go it will be a dense piece of snow to ride.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

The lower half of the snowpack is garbage, and will be for the distant future. Facets, crusts and depth hoar make for a very unsupported base for the snowpack. Large, avalanche prone features are out for now.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Jan 11th, 2017 4:00PM