Avalanche Forecast

Issued: Dec 29th, 2014 8:01AM

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.

Avalanche Canada triley, Avalanche Canada

Avalanche danger is expected to remain at Considerable during the forecast cold and clear weather for the end of the year.

Summary

Confidence

Fair

Weather Forecast

Clear and cold overnight with alpine temperatures dropping to about -25 and moderate Northeast winds. Winds becoming strong Northwest during the day on Tuesday and alpine temperatures rising up to about -16 under clear skies. Cold and clear with light Westerly winds on Wednesday. Increasing cloud on Thursday with a chance of light snow in the afternoon.

Avalanche Summary

No new avalanches reported. Natural avalanche activity is tapering off as the storm ends and the storm slab settles. Human triggering continues to be likely to very likely due to the storm slab sitting on a hard sliding surface with a weak layer of surface hoar at the interface.

Snowpack Summary

Some new windslab has formed at higher elevations that is 20-40 cm thick, easy to trigger, and may step down to the mid-December surface hoar. The touchy mid-December surface hoar layer is now buried below a 50-90 cm consolidated slab that developed during last weeks storm. Below 2100 m this slab sits on a thick, solid crust/ surface hoar combination and has been acting as a perfect sliding layer. A hard rain crust with facets from early November is buried over 1 m down and is currently unreactive, however; triggering from shallow rocky and unsupported terrain remains a concern.

Problems

Persistent Slabs

An icon showing Persistent Slabs
The mid-December crust and surface hoar layer is now buried between 50-80 cm and continues to be a concern for triggering by light additional loads like a skier/rider.
Use conservative route selection, dig down and test weak layers before committing.>Stick to simple terrain, small features with limited consequence and be aware of what is above you at all times.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 5

Wind Slabs

An icon showing Wind Slabs
Northerly winds continue to transport the recent snow into pockets of windslab in the alpine and at treeline. Watch for areas of reverse loading due to the change in wind direction since the last storm that came out of the Southwest.
Avoid freshly wind loaded features.>Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Dec 30th, 2014 2:00PM