Avalanche Forecast

Issued: Feb 1st, 2016 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.

tim mcallister, Parks Canada

Jasper.

Keep an eye out for buried wind slabs on north and north east aspects in the alpine.

Summary

Weather Forecast

Cool temperatures, with freezing levels remaining below 1100m for next 3 days. Light Southwest wind, gusting to moderate. Light scattered flurries amounting to less than 5cm.

Snowpack Summary

Up to 35 cm fell in the Icefields area on Thursday with moderate SW winds building touchy soft slabs on lee slopes at tree line and above. Wind slabs to 90cm think overlying weak facets on north aspects found. Rain below tree line- possible rain crusts.

Avalanche Summary

Saturday natural activity noted up to size 3 running relatively far on a variety of aspects mainly in alpine. Explosive work was mixed results with sluff's to soft slabs up to size 2.5 on the range of aspects and elevations. On Friday, a skier accidental at Parkers Ridge, size 3, 1 involvement, no injuries. Depth 50-150cm x 400m x 400m.

Confidence

Due to the number of field observations on Monday

Problems

Persistent Slabs

35 cm of storm snow from Thursday continues to build into a slab overlying a weak facetted snowpack or decomposed surface hoar layer.

Be aware of thin areas that may propogate to deeper instabilites.Use caution on open slopes and convex rolls at treeline where buried surface hoar may be preserved.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

Triggering is likely in steep terrain. Thursdays' new snow added to this problem in many locations.

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 2nd, 2016 4:00PM