Avalanche Forecast

Issued: Jan 28th, 2015 4:00PM

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

a.l. horton, Parks Canada

Jasper.

The avalanche cycle has tapered off but alpine conditions have not changed significantly. A melt freeze crust has stabilized conditions below treeline.

Summary

Weather Forecast

Mild and dry conditions will continue on Friday. Around 10 cm of snow will start falling on Friday night with light west winds through Saturday. Cold air moves into the area on Saturday night bringing clear crisp temperatures on Sunday.

Snowpack Summary

There is a melt freeze crust at treeline to valley bottom. The crust weakens into treeline. In the alpine, heavier snow sits over a persistent weak layer dating to Dec 20th.

Avalanche Summary

The avalanche activity has slowed with the cooler temperatures. Several slab avalanches to size 2.5 from the past 24 hrs were observed on easterly aspects around 2400 m. Previous loose wet avalanches were numerous on lower elevation westerly aspects and pin wheeling was observed up to 2300 m.

Confidence

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

Problems

Deep Persistent Slabs

This weakness is sitting at or close to the ground. Numerous large avalanche failing on this layer during Wednesday's avalanche control.

Be aware of the potential for full depth avalanches due to deeply buried weak layers.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Persistent Slabs

Forecasters have had easy test results on this layer today. The tricky thing about this layer is that it is not widespread but can be found in sheltered areas.

Choose well supported terrain without convexities.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Jan 29th, 2015 4:00PM