Avalanche Forecast

Issued: Dec 3rd, 2011 9:38AM

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

jlammers, Avalanche Canada

South Coast.

Summary

Confidence

Fair - Due to limited field observations

Weather Forecast

Mostly clear skies are forecast sunday through tuesday with light to moderate winds from the northwest. On sunday, freezing levels are expected to sit at or near surface, but a spike in temperature is forecast for monday with freezing levels reaching 3000m. On tuesday, freezing levels are expected to dip back to around1500m.

Avalanche Summary

No recent avalanche observations. We have had limited info from this region. Any field reports are welcome and can be sent to forecaster@avalanche.ca.

Snowpack Summary

Wind slabs probably still exist in lee and crossloaded terrain. Use increased caution on steep, sun-exposed slopes during forecast warming periods.There is a solid rain crust, down 15-30cm below 1800m, which has greatly reduced the likelihood of avalanches at lower elevations.A surface hoar layer has been observed down approximately 45cm in the Duffey Lake area and more is growing on the current snow surface. A facet layer near the base of the snowpack continues to give sudden collapse ("drops") results in snowpack tests. These layers have not produced any avalanches that I am aware of, but it makes sense to keep them on your radar.Continued caution is recommended in shallow, unsupported snowpack areas (lots of rocks or small trees poking through), especially on sun exposed slopes if the sun has any kick.

Problems

Wind Slabs

Watch for windslabs on lee and cross-loaded aspects.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Persistent Slabs

Weak layers of facets and depth hoar may be lurking deep in the snowpack in some parts of the region. The chances of triggering any of these weaknesses is decreasing; however, increased caution is recommended in steep, unsupported, rocky terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

2 - 4

Valid until: Dec 4th, 2011 8:00AM