Avalanche Forecast

Issued: Dec 5th, 2014 7:34AM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Persistent Slabs and Storm Slabs.

pgoddard, Avalanche Canada

South Columbia.

Avalanche danger has improved since last weekend, but a skier or sledder could still trigger a large avalanche in specific terrain.

Summary

Confidence

Fair - Intensity of incoming weather systems is uncertain

Weather Forecast

Saturday: Light snow. Light to moderate SW winds. A layer of warm air may form at mountain height, while the valleys remain cooler.Sunday: Light snow. Light to moderate SW winds. The layer of warm air aloft may persist. Monday: Light snow. Light to moderate SW winds. Warming up at all elevations late in the day.

Avalanche Summary

Two recent slabs were observed in the far south of the region. These appear to have failed on a hard crust layer buried about a metre down. In general, avalanche activity has eased but there is still the chance of triggering a large avalanche on a persistent weak layer.

Snowpack Summary

Surface: Friday's light snow hides surfaces including wind slabs (variable in distribution); surface hoar, which has grown large in sheltered spots; and sun crusts on steep south-facing slopes.Upper-mid pack: Anywhere from 5-30 cm of settling snow sits on a crust which formed in late November. This crust is supportive above about 1800m, but is breaking down at lower elevations. About 1m down, a weak layer of surface hoar and/or facets can be found in some locations. Snowpack tests on this layer are showing improving results, but in some locations "pops and drops" indicate this beast could still be touchy.Lower pack: A thick rain crust from early November is buried over a metre down.

Problems

Persistent Slabs

The chances of triggering a persistent slab have decreased, but potential consequences remain high.

Avoid common trigger zones including thin snowpack areas, near rocky outcrops, and steep alpine slopes.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 5

Storm Slabs

Snow and wind may create new slabs over the weekend. These may become more reactive as alpine temperatures rise.

Be cautious as you transition into wind affected terrain.>Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Dec 6th, 2014 2:00PM