Avalanche Forecast

Issued: Feb 24th, 2014 4:00PM

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

snow safety, Parks Canada

Banff Yoho Kootenay.

The Feb 10th layer is persistent and remains a significant concern in the snowpack. Enjoy the great ski conditions but stick to moderate terrain and don't let the clear skies lure you into bigger lines until the conditions improve. CJ

Summary

Weather Forecast

Alpine temperatures down to -15'C tonight then warming to -8'C Tuesday. A warming trend is expected for Wednesday and Thursday with alpine temperatures between -10'C and 0'C. Continued clear skies, light Northerly winds and no new precipitation is expected for the next three days.

Snowpack Summary

25-60cm of recent storm snow is sitting over the Feb10th layer of facets, sun crust and surface hoar. Field tests continue to show an easy to moderate sudden collapse at this interface. Some isolated wind slabs are present in the alpine. If triggered these wind slabs could step down to the Feb 10th interface.

Avalanche Summary

The natural avalanche cycle has subsided but skier triggered slabs remain likely. A skier triggered (Class 1) from yesterday was observed at treeline on the exit out of Purple Bowl in the Lake Louise area. We have also had other skier triggered, skier remote, and natural avalanches up to Class 2 in the last 72 hours on the Feb 10th interface.

Confidence

Problems

Persistent Slabs

The natural cycle is over but the Feb 10th interface down 25-60 cm is still producing easy to moderate results, with lots of whumphing and some recent skier triggered avalanches. Stick to moderate angled, well supported terrain until things improve.

Avoid unsupported slopes.Avoid open slopes with any steepness over 30 degrees.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

Recent winds have left isolated wind slabs in lee alpine terrain. If triggered these wind slabs could step down to the Feb 10th storm snow interface resulting in large avalanches.

If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Use caution in lee areas in the alpine and treeline. Recent storm snow has formed touchy slabs.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Feb 25th, 2014 4:00PM