Avalanche Forecast

Issued: Feb 23rd, 2017 4:00PM

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

garth lemke, Parks Canada

Jasper.

Whumphs notes in our region. and remote skier triggering of avalanches continue amongst our nearest neighbors. The weak base will persist for sometime. Cautious decisions are key as initiating an avalanche would be severe consequences.

Summary

Weather Forecast

Light snow now to Sunday. Friday will be light N winds and cold -20 temperatures. Saturday will be light Westerly and shifting Northerly Sunday.

Snowpack Summary

Windslabs exist at TL and ALP. Winds now shifting light Northerly. A rain crust is below 1900m. A dense upper snowpack overlies a weak faceted base making for unpredictable dangerous avalanche conditions. Feb 10 SH layer may be 40cm deep yet its reactivity remains dormant.

Avalanche Summary

Skiers report whumphs in Whistler creek drainage on Thursday. On Feb 17 several size 2-3 avalanches were triggered by skiers from a significant distance away in the McCarib Pass area. Not much has changed in terms of the snowpack characteristics.

Confidence

The weather pattern is stable

Problems

Deep Persistent Slabs

Widespread whumphing and shooting cracks in previously un-skied terrain. Recent natural activity and remote triggering of this weakness resulted in avalanches up to size 3 failing on the weak faceted snowpack. Caution is recommended.

Be aware of thin areas that may propogate to deeper instabilites.Watch for shooting cracks or stiffer feeling snow. Avoid areas that appear wind loaded.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

Previous 25cm snow and moderate SW winds have added to the windslab problem in the alpine and open tree-line features.

Use caution in lee areas. Recent wind loading have created wind slabs.Be aware of the potential for wide propagations due to the presence of hard windslabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Feb 24th, 2017 4:00PM