Avalanche Forecast

Issued: Dec 4th, 2014 8:32AM

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

I would veer away from thin snowpack areas, rocky outcrops and large steep alpine slopes which didn't avalanche last week.

Summary

Confidence

Poor - Due to the number of field observations

Weather Forecast

Warm air from the Pacific will push in, bringing milder temperatures but not much precipitation in the short term.Friday: Light snow. Winds increasing to moderate SW. Staying cool. Saturday: Light snow. Ridgetop winds increasing to moderate-strong SW. A layer of warm air may form at mountain height, while the valleys remain cool.Sunday: Light snow. Light to moderate S winds. The layer of warm air aloft may become more entrenched.

Avalanche Summary

We haven't had any new reports of avalanche activity. This may be due to a lack of observations rather than actual conditions. If you have any observations, please send them to forecaster@avalanche.ca.

Snowpack Summary

Approximately 1m of settling storm snow sits on weak crystals which formed throughout early and mid-November. These weak crystals include facets on a hard rain crust, and surface hoar (which may also sit on a crust on steep southerly slopes). Snowpack data from the Cariboo region is very limited at the moment, but I expect these layers are reacting similarly to the North Selkirk/Monashees because the formation conditions were generally the same. Recent snowpack tests suggest these layers can still be human triggered in some locations, and if triggered, are capable of producing wide propagations and large avalanches. Recent variable winds may have redistributed surface snow creating dense wind slabs in exposed terrain.

Problems

Persistent Slabs

An icon showing Persistent Slabs
Weak crystals are buried in the upper metre or so of the snowpack. Deep avalanches on these layers are most likely to be triggered by people from thin snowpack areas, near rocky outcrops, and on steep alpine slopes.
Avoid convexities or areas with a thin or variable snowpack.>Conditions may have improved, but be mindful that deep instabilities are still present.>Be aware of the potential for large, deep avalanches due to the presence of buried weak layers.>Be cautious as you transition into wind affected terrain.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 5

Valid until: Dec 5th, 2014 2:00PM