Avalanche Forecast

Issued: Nov 30th, 2012 9:23AM

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

jlammers, Avalanche Canada

South Columbia.

Summary

Confidence

Fair - Intensity of incoming weather is uncertain on Saturday

Weather Forecast

Saturday: Moderate snowfall with locally heavy accumulations / Moderate southwest winds with strong gusts / Freezing level at 1200mSunday: Light snowfall / Light southeasterly winds / Freezing level @ 1200m Monday: Light to moderate snowfall / Moderate to strong southwesterly winds / Freezing level @ 1100m

Avalanche Summary

No recent avalanche activity to report. We welcome all field observations at forecaster@avalanche.ca.

Snowpack Summary

As of Friday, between 20-30cm of recently fallen snow sits over a variety of surfaces that may include surface hoar, a sun crust on steep solar aspects, and well settled storm snow from last week. Forecast wind and snowfall for Friday night and Saturday should significantly increase the size and reactivity of this developing wind/storm slab.Deeper in the snowpack you might find a thin, spotty surface hoar layer about 85cm down. As well, the early November rain crust now sits over 100cm down in most locations (at treeline and above) and may exist in combination with facets. These layers seem to have been unreactive in recent days, but may have the potential to 'wake-up'.The snowpack depth in the alpine ranges from 130-225 cm. Treeline near 150 cm.

Problems

Storm Slabs

Snow and wind forecast for Friday night and Saturday will significantly add to the size and reactivity of a developing wind/storm slab. This avalanche problem overrides a variety of potentially weak surfaces.

Avoid all avalanche terrain during periods of heavy loading from new snow and wind.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 5

Persistent Slabs

Although the likelihood of a release is low, the consequences of a persistent slab avalanche could be significant. These layers may wake-up with additional loading.

Choose well supported terrain without convexities.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 6

Valid until: Dec 1st, 2012 2:00PM