Avalanche Forecast

Issued: Jan 29th, 2015 8:12AM

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

Avalanche Canada pgoddard, Avalanche Canada

Cooling has improved avalanche danger, but deep avalanches remain a possibility, especially in thin snowpack areas at high elevations.

Summary

Confidence

Fair

Weather Forecast

A few cm snow are forecast for Friday night. A second pulse of snow (5-15 cm) is due on Sunday. Freezing level is at valley floor during the nights and rising to around 800 m by day. Winds are generally light for the next three days.

Avalanche Summary

As the temperature drops I expect that avalanche activity will slow down. The recent snow, rain, and wind were a great test of buried persistent weaknesses in the snowpack and resulted in a widespread avalanche cycle. The mid-January surface hoar layer was responsible for the majority of the recent avalanche activity although there have been reports from the Selkirks of occasional releases to ground and on the mid December layer.

Snowpack Summary

Variable crusts exist at most elevations, ranging from breakable to supportive. Above about 2300 m, you might find some wind-affected snow and cornices. The mid-January surface hoar remains a concern and can be found down between 30 and 80 cm. In some locations it has reportedly gained quite a bit of strength, but in other spots it still produces sudden (pops) results in snowpack tests. The mid-December surface hoar layer is now 80 to 140cm below the surface and has become unlikely to trigger (but still has the potential for a large avalanche if triggered).

Problems

Persistent Slabs

An icon showing Persistent Slabs
A layer of surface hoar buried in the upper snowpack remains a concern, especially at treeline and higher. A large trigger, like an avalanche in motion or cornice fall, could trigger a deeper persistent weakness.
Avoid convexities or areas with a thin or variable snowpack.>Do not travel on slopes that are exposed to cornices overhead.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 5

Valid until: Jan 30th, 2015 2:00PM