Avalanche Forecast

Issued: Feb 11th, 2012 9:58AM

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

Avalanche Canada triley, Avalanche Canada

Summary

Confidence

Good - -1

Weather Forecast

A ridge of high pressure is expected to rebuild on Sunday over the interior mountains. Moisture that is left over from the weak system on Saturday will continue to cause mid-level cloud and isolated flurries on Sunday that are expected to bring a total of 3-5 cm. Winds are expected to continue to be light in the Cariboos and start to swing to the northwest in the afternoon. The freezing level is forecast to rise to about 1200 metres on Sunday and drop overnight to about 900 metres. Treeline maximum temperatures should be about -4.0 on Sunday and Monday. A weak Pacific system is expected to run into the ridge of high pressure on Monday that should cause some light snowfalls accumulating about 5 cm. The wind should change to north on Monday night as more high pressure moves across the interior. Temperatures should drop down to about -15.0 in the alpine briefly on Tuesday morning. Clear skies and strong solar radiation is expected during the day on Tuesday, however northwest winds should help to keep alpine maximum temperatures close to -10.0 on shaded aspects.

Avalanche Summary

There are a few reports of natural solar releases up to size 2.0 on South and Southeast aspects around 2000 metres from Friday.

Snowpack Summary

There is a thin layer of new snow above the recently developed surface hoar (120209 SH). Some areas have reported that the surface hoar had grown to 50 mm before being buried. Some thin windslabs have developed due to down flowing air on large glaciated features. A melt-freeze crust has developed on solar aspects at all elevations, and on all aspects below about 1400 metres. The mid-pack is generally well settled. There is some concern that large loads like cornices may trigger the Jan. 20th facet layer. Some shallow snowpack areas may continue to have a weak layer of basal facets near the ground.

Problems

Cornices

An icon showing Cornices
Cornices are large and may become weak and fall off naturally. Large loads like cornices may trigger slab avalanches on the slopes below.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 6

Valid until: Feb 12th, 2012 3:00AM