Avalanche Forecast

Issued: Mar 2nd, 2012 9:40AM

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

Avalanche Canada triley, Avalanche Canada

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain on Saturday

Weather Forecast

A warm front is forecast to move over the central and south coast on Friday night, bringing moderate precipitation and strong westerly winds. The winds are expected to peak at about 100 km/hr sometime in the early morning. Expect about 5-10 cm of snow overnight and another 5-10 cm during the day on Saturday. The freezing level on Saturday should rise to about 1200 metres. Snow is expected to continue on Sunday bringing another 5 cm and strong westerly winds. Periods of heavy snowfall are expected on Monday.

Avalanche Summary

Several size 1.0 avalanches have been reported from the Duffey Lake area. As reports of natural activity have started to taper off, rider triggers are likely and still occurring. Backcountry travel requires local knowledge, extensive experience and training. The obvious clues that show snowpack instability may not be there. You need to dig deep, do your detective work and make good decisions. With forecast snow, wind and rising freezing levels, you can expect to see the danger ratings elevate over the weekend.

Snowpack Summary

New windslabs are developing from new snow and strong westerly winds. There are reports that down 30-40 cm is a preserved stellar interface that is providing easy, sudden planar test results, and a rutschblock score of 2 (whole block failing). The mid February interface (crusts at lower elevations, and buried surface hoar in sheltered locations) is down approximately 60 cm below the surface. Below this the lower snowpack is well bonded and strong.

Problems

Wind Slabs

An icon showing Wind Slabs
New snow and strong forecast westerly winds are expected to develop windslabs that may be easily triggered.

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

2 - 5

Persistent Slabs

An icon showing Persistent Slabs
Forecast snow through the weekend may add to the current storm snow instabilities; especially in areas that overlie preserved stellars, facets, buried surface hoar and crusts. Avalanches sliding on this layer may be large and destructive.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

3 - 6

Valid until: Mar 3rd, 2012 8:00AM