Avalanche Forecast

Issued: Nov 28th, 2012 8:40AM

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.

burke.duncan, Alberta Parks

Kananaskis.

Not much change observed on Wednesday but change is coming with new snow and increasing winds leading into Friday and the weekend so look for Avalanche Danger to rise, especially in the Alpine elevation zone..

Summary

Confidence

Good

Weather Forecast

The ridge of high pressure is breaking down with 10-15cm of new snow expected by later on Friday. Winds will increase into strong to extreme range over the next 48 hours.

Avalanche Summary

A few loose snow slides up to size 2.0 were observed on steep N and E aspects in the alpine in the Highwood Pass area but little new activity has been observed elsewhere.

Snowpack Summary

A couple of new snow profiles again today further highlighted weaknesses associated with the November raincrust.Â Compression tests continued to produce results below the rain crust in the moderate range. There is also evidence of on-going wind slab formation in the alpine, but this is not present in all locations.

Problems

Wind Slabs

Pockets of wind slab are present in lee and cross loaded features in the alpine and isolated areas at tree line. NW winds over the past few days resulted in some loading onto S and SE aspects. A few cornice failures have also been observed.

Assess start zones carefully and use safe travel techniques.>Avoid convexities or areas with a thin or variable snowpack.>Avoid cross loaded features.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 5

Persistent Slabs

The Nov rain crust persists about 30cm off the ground throughout the forecast area and is reactive to stability tests in the moderate range. Avalanches in the upper snowpack may step down to this weakness.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>Be aware of the potential for full depth avalanches due to deeply buried weak layers.>Be aware of thin areas that may propagate to deeper instabilites.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 5

Valid until: Nov 29th, 2012 2:00PM