Avalanche Forecast

Issued: Dec 26th, 2014 8:18AM

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

swerner, Avalanche Canada

Cariboos.

Conservative decision making and disciplined terrain use is the name of the game when these tricky avalanche conditions persist. Check out the new Forecaster Blog @ avalanche.ca.

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain

Weather Forecast

A weak system will slide down the coast and start to affect the Interior on Saturday bringing snowfall amounts 10-20cm. Ridgetop winds will be light-moderate from the west, switching to a northerly flow by Sunday. Alpine temperatures will hover around -15 then drop to -18 later Sunday. Conditions will remain cold and dry through Tuesday.

Avalanche Summary

Natural avalanche activity has tapered off and skier/ rider triggered avalanches are the name of the game. On Thursday several skier triggered avalanches size 1 were reported. These failed on the buried surface hoar layer 45 cm down on NE aspects in between 1400-1600 m.

Snowpack Summary

A cohesive slab (40-80 cm) sits above a touchy surface hoar layer that was buried mid-December. Below 2100 m this slab sits on a thick, solid crust/ surface hoar combination and has been acting as a perfect sliding layer. Persistent slabs will be very touchy to the weight of a skier and rider, especially in wind effected areas. 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

A very touchy surface hoar layer is buried by a 40-80 cm thick persistent slab. This layer is widespread, and is easily triggered by skiers and riders. Remote triggering with wide propagation remains a concern.

Stick to simple terrain, small features with limited consequence and be aware of what is above you at all times.>Use conservative route selection, dig down and test weak layers before committing.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 5

Wind Slabs

Wind slabs can be found on leeward slopes and behind terrain features.

Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Dec 27th, 2014 2:00PM