Avalanche Forecast

Issued: Nov 22nd, 2012 4:34PM

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

mike eder, Parks Canada

Jasper.

Be aware of early season hazards that are buried by the recent snowfalls.

Summary

Weather Forecast

Another frontal system is expected to bring around 20cm of snow accompanied with steady moderate SW winds to the icefields area. Jasper townsite is expected to receive only a few centimeters on Friday night.

Snowpack Summary

Snowpack on a south aspect at treeline is 60cm with facets between two crusts and a moist layer at the ground.Â Moderate tests showed a weakness in the facets just above the november 6th crust.

Avalanche Summary

Several sz 2 -3 slab avalanches in high alpine on cross loaded gully and terrain features on North through West to Southwest aspects. Numerous loose snow avalanches originating in rock bands on Westerly aspects from 2600 - 2900meters.

Confidence

Timing, track, or intensity of incoming weather system is uncertain

Problems

Wind Slabs

This layer produced several avalanches from size 2 -3. They were limited to lee and cross loaded features but a wide range of aspects in the alpine.

Avoid unsupported slopes.Avoid cross loaded features.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Persistent Slabs

A variety of old surface layer shears can be found in field tests. No avalanches have been observed on these layers. A test profile on Parker south on Wednesday showed moderate sudden planar results.

Avoid shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Nov 23rd, 2012 4:00PM