Avalanche Forecast

Issued: Dec 24th, 2014 4:00PM

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

rupert wedgwood, Parks Canada

Jasper.

Tiny Tim and the Ghost of Christmas Past found good turns on Hilda Ridge, Merry Christmas one and all.

Summary

Weather Forecast

No significant snowfall is forecast until the weekend when up to 10cm may arrive in the Icefields area. Temperatures will drop over Christmas with overnight lows in the low teens but warming during the day. Over the next 24 hours winds will remain light from the West and at upper elevations NW. Over the weekend these are forecast to increase.

Snowpack Summary

Wind slab forming on lee alpine ridge lines. Large surface hoar crystals formed last week are being buried by new snow. This layer is more likely to be found on sheltered slopes at tree line and below. The interface between the strong mid-pack and weaker basal facets is most susceptible to human triggering from shallow rocky areas.

Avalanche Summary

Three new avalanches were recorded in the Columbia Icefields area. The events were size 2 thin storm slabs and class 1.5 point releases from steep slab alpine terrain.

Confidence

The weather pattern is stable

Problems

Wind Slabs

Wind loading producing soft slabs on lee features at and above treeline. A field team on the 24th found a generally stable snowpack with hard and moderate shears in the upper snowpack at alpine elevations. Good skiing in sheltered spots.

Be careful with wind loaded pockets while approaching and climbing ice routes.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

This weak layer exists below a strong mid-pack at treeline and sub-alpine elevations. Surface slides or cornice collapse could trigger this deep persistent weakness.

Carefully evaluate and use caution around thin snowpack areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

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