Avalanche Forecast

Issued: Feb 20th, 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.

Conditions remain unpredictable with whumphing noted. Consequences of being caught would be severe. Be cautious in recently opened Caribou closure areas.

Summary

Weather Forecast

Sun and cloud with light flurries the next few days. Temperatures are cooling slightly into the -12 to -16 range. Winds may shift Northerly on Wednesday. No significant snow is expected.

Snowpack Summary

25cm new snow and warm temperatures last week at the Columbia Icefields with 35km/hr SW winds built a windslab at TL and ALP. A rain crust exists below 1900m. The dense upper snowpack overlies a weak faceted lower pack making for unpredictable and dangerous avalanche conditions.

Avalanche Summary

On Friday several size 2-3 avalanches were remote triggered by skiers a significant distance away in the McCarib Pass area. Several avalanches to Sz 3 occurred Saturday along the Parkway with one dusting the highway from Mt. Wilson. Widespread whumphing and shooting cracks were noted in the Whistler creek area on all elevations.

Confidence

Problems

Deep Persistent Slabs

Widespread whumphing and shooting cracks in previously un-skied terrain. Recent natural activity up to Sz 3 failing on the weak faceted snowpack.

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

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

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

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

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Feb 21st, 2017 4:00PM