Avalanche Forecast

Issued: Apr 4th, 2013 9:57AM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Loose Wet, Wind Slabs and Cornices.

mbender, Avalanche Canada

Cariboos.

Summary

Confidence

Fair - Freezing levels are uncertain on Friday

Weather Forecast

Friday: A low pressure system will move over the interior late Thursday through Friday bringing moderate to locally heavy precipitation. Freezing levels will be around 1400m. Northern portions of the region may be under the influence of an arctic front. In areas where this is the case freezing levels will be at valley bottom. Winds light to moderate from the southwest.Saturday: Overcast with light precipitation possible. Winds moderate from the southwest. Freezing level 1600m. Sunday: A break between off-shore weather systems will bring overcast skies with a trace to light amounts of snow and some possible sunny breaks.

Avalanche Summary

Natural wet-loose avalanches up to Size 2.5 continue to be reported on solar aspects when the sun has been shining.

Snowpack Summary

At upper elevations 10-15cm of new snow is covering a crust or moist snow. In some places in the alpine and at treeline this new snow may have buried a recently formed layer of surface hoar or facets. At lower elevations (below 1700m) rain has made the snow surface wet or moist.Â New snow combined with wind will have made large cornices even bigger.The March 10th surface hoar/crust interface is buried more than 100cm in most places. Although unlikely to trigger, this deep persistent weakness remains a concern because of the potential for very large avalanches particularly with heavy triggers such as cornice falls or lighter triggers on solar aspects where the crust is more prevalent. Below this the snowpack is strong and well settled.

Problems

Loose Wet

With little re-freezing overnight, loose wet avalanches will run on solar aspects if there is rain falling or even short periods of intense solar radiation. Wet slab avalanches are also possible.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>Avoid travelling on slopes which are becoming wet due to rain, warm temperatures, or sun.>Be alert to conditions that change with elevation.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 4

Wind Slabs

New snow combined with moderate winds have created fresh windslabs in the lee of terrain features.

Be cautious as you transition into wind affected terrain.>Use ridges or ribs to avoid pockets of wind loaded snow.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Cornices

New snow and wind have made large cornices even bigger.

Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 6

Valid until: Apr 5th, 2013 2:00PM