Avalanche Forecast

Issued: Jan 10th, 2017 4:00PM

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

mark herbison, Parks Canada

Jasper.

Highway 93N will be closed from 10am-5pm MST on Wednesday for Avalanche Control from Saskatchewan River Crossing to Parker Ridge. No Skiing or Climbing in the area.

Summary

Weather Forecast

A ridge of high pressure has rebuilt, clear skies with no snow in the forecast, temps will gradually rise overnight and into Wednesday reaching a high of -12 in the alpine. Light North West winds will shift to moderate from the West on Thursday.

Snowpack Summary

10-15cm of new snow has been redistributed by moderate NW winds into slab on lee and cross loaded features. The new windslab overlies a shallow, faceted and weak snowpack. The Nov. crust can still be found about 30 cm up from ground but is faceting into large depth hoar. The upper half of the snowpack has layers of wind slab and facets.

Avalanche Summary

Numerous size 1-2.5 loose dry avalanches on all aspects and elevations, but mainly out of steep, rocky terrain features. One sz 2.5 slab avalanche pulled out on Mt. Cirrus, several gullies North of Polar Circus, running mid path above the cliff face.Ice Climbers be aware, the cold temps have made free hanging ice brittle and they are breaking off.

Confidence

Due to the number and quality of field observations

Problems

Wind Slabs

Various wind directions over the past 72hrs have created windslab on most aspects Treeline and above and rests upon a weak, faceted snowpack. Recent natural activity observed in steep cross loaded gullies.

Watch for areas of hard wind slab in steep alpine features.Caution in lee and cross-loaded terrain near ridge crests.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Loose Dry

Cold temps have facetted the snowpack and is causing it to lose cohesion and release loose dry avalanches in steep terrain. The 10-15cm of new snow will add to this problem. This is concerning for ice-climbers and skiers in confined/exposed terrain.

Be very cautious with gully features.Use caution above cliffs where small avalanches may have severe consequences.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 11th, 2017 4:00PM