Avalanche Forecast

Issued: Dec 27th, 2011 8:26AM

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

pgoddard, Avalanche Canada

Cariboos.

Summary

Confidence

Poor - Forecast snowfall amounts are uncertain

Weather Forecast

Tuesday night: 5-10cm. Wednesday: 2-5cm. Freezing level rising to 1400m. Strong south-west winds. Thursday: 5-10cm. Strong south-west winds. Friday: Generally drier conditions. Weather forecasters have low confidence at the moment (read more in the Forecaster's Blog). Be prepared for local variations in weather, and assume the avalanche danger is higher than posted in areas with enhanced snow, rain or wind.

Avalanche Summary

A size 2 naturally-triggered storm slab was observed on a west aspect at 2400m.

Snowpack Summary

20-40cm of total storm snow has been reported. Wind slabs exist on slopes lee to the west in the alpine and in open areas at treeline and below. A surface hoar/facet/crust interface is buried anywhere from 40- 80cm deep. Avalanche activity on this layer has slowed, but it remains a concern as snow-loading gradually builds this week, particularly on slopes which did not avalanche last week. This layer is still showing easy results in some areas. A sun crust is also buried in the alpine on some steep south and west aspects. The mid-pack is generally strong and well settled.

Problems

Wind Slabs

Up to 40cm of storm snow has been shifted by the wind onto lee slopes. Be alert for wind slabs behind ridges and terrain breaks and in gullies.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Persistent Slabs

A buried surface hoar layer remains a concern. It is now buried about 40-80cm deep.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 5

Valid until: Dec 28th, 2011 8:00AM