Avalanche Forecast

Issued: Dec 14th, 2016 5:38PM

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

Parks Canada Ruari Macfarlane, Parks Canada

Ice climbers: in the Front (Eastern) Ranges, avalanche hazard is higher than rated. Avoid hard, cardboard-like Wind Slab, especially around terrain traps like cliffs and gullys.

Summary

Weather Forecast

Thursday: Light upslope event : Cloudy with light snowfall. A minor inversion sees alpine temps around -17, with Valley Floor temps falling into the -20's.  Light- Moderate Easterly winds.Friday: Slowly clearing, chance of flurries, -27 at Treeline. Moderate NE winds slowly easing.Saturday: Clear. Moderate-Strong Westerly winds, -25 with inversion.

Snowpack Summary

30cm of storm snow has been blown into windslabs (or scree) at all elevations in the East, but remains low density in the West. This overlies several buried wind slab layers, beneath which are dense facets bonding well to a crust near ground.  Snowpack tests at Treeline indicated some potential for shears in the facets below the wind slabs.

Avalanche Summary

On Tuesday, Wind Slabs in gulleys in Eastern areas were observed to be touchy, often on cross-loaded gully walls (terrain traps). On Wednesday, several large avalanches were observed: A Size 2 Cornice failure, several size 2 Wind Slabs on N and NE facing Alpine slopes, and a fresh Size 2.5 Wind Slab on a NE aspect slope at 2350m.

Confidence

Wind speed and direction is uncertain on Friday

Problems

Wind Slabs

An icon showing Wind Slabs
Wind slabs are currently a problem in the Alpine in Western Areas, and on all snowy slopes in Eastern areas.  Watch for this problem to move to S and W facing slopes if we see moderate NE winds Thursday-Friday.
Be careful with wind loaded pockets while approaching and climbing ice routes.Use caution in lee areas in the alpine. Recent wind loading have created wind slabs.

Aspects: North, North East, East.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Dec 17th, 2016 4:00PM