Avalanche Forecast

Issued: Feb 2nd, 2016 4:00PM

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

Max Darrah, Parks Canada

Jasper.

Natural avalanches and touchy conditions are still being reported, particularly at treeline. The alpine is also active with loose dry activity on solar aspects and a weak midpack trying to support recent loading from wind and snow.

Summary

Weather Forecast

Cool temperatures, with freezing levels remaining below 1000m for Wednesday then a gradual warming trend towards the weekend. Light Southwest wind, gusting to moderate. Light scattered flurries amounting to less than 5cm by Friday evening.

Snowpack Summary

Recent storm snow has formed new windslabs in the alpine and at treeline, mainly on North Easterly aspects below ridge crests. These slabs add load to a mainly weak and facetted midpack that has a layer of concern down about 60cm at an interface of facets and new snow.

Avalanche Summary

1 new natural slab avalanche noted in the Mt Diadem area - East aspect, 2100m. 80m wide, ran 50m, and appeared to be about 60-90cm deep, most likely sliding on facets and possibly decomposing surface hoar. Several loose dry slides to size 2.5 out of steep rocky terrain in the alpine, entraining mass especially where confined by terrain.

Confidence

Due to the number of field observations

Problems

Persistent Slabs

35cm of storm snow from Thursday has formed a slab overlying a weak facetted snowpack or decomposed surface hoar layer.

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

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

Although this problem seems to be improving, triggering is still likely in steep terrain.

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

Loose Dry

Several loose slides were observed out of steep rocky terrain, primarily on solar aspects in the alpine. These avalanches entrained mass, especially where confined by terrain such as gullies and drainages.

The volume of sluffing could knock you over; choose your climb carefully and belay when exposed.Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Feb 3rd, 2016 4:00PM