Avalanche Forecast

Issued: Dec 23rd, 2011 8:56AM

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

Avalanche Canada pgoddard, Avalanche Canada

Summary

Confidence

Fair - Intensity of incoming weather is uncertain on Monday

Weather Forecast

Saturday: Light snowfall with the freezing level at valley bottom. Moderate-strong westerly winds.Sunday/Monday: Weak disturbances could bring further light snowfall. Expect freezing levels to hover between 1100m and valley bottom. Strong south-westerly winds.

Avalanche Summary

Recent reports include isolated human triggered Size 1 thin soft wind slab avalanches running on large surface hoar, on south through east facing treeline slopes.

Snowpack Summary

Recently developed surface hoar and near-surface facets are likely to get gently buried by light snowfall over the next few days, potentially creating a weak interface which could become reactive with enough new load from snow and/or wind-transport.In the meantime, the snowpack is relatively well bonded, except for buried surface hoar layers in the upper 15cm (with sudden test results on these layers in some locations) and soft and hard wind-slabs on certain slopes in the alpine and around treeline. Facets at the base of the snowpack could create a deep persistent slab problem that deserves attention in shallow snowpack areas on planar rocky slopes.

Problems

Wind Slabs

An icon showing Wind Slabs
Watch out for wind slabs below ridge crests, behind terrain breaks, and in cross-loaded gullies.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Dec 24th, 2011 8:00AM