Archived

Avalanche Forecast

Dec 26th, 2014–Dec 27th, 2014

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

3: Considerable

The avalanche danger rating below treeline will be considerable

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: Purcells.

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.

Confidence

Fair - Due to the number of field observations

Weather Forecast

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

Avalanche Summary

Natural avalanche activity has tapered off, however; on Thursday an explosive triggered size 2.5 slab avalanche initiated in the mid-December surface hoar and stepped down to the early November rain crust. Yikes! Definitely something to keep on your radar.

Snowpack Summary

Storm snow totals 30-70 cm above a very touchy surface hoar layer that was buried mid-December. Below 2100 m this storm slab sits on a thick, solid crust/ surface hoar combo and has been acting as the perfect sliding layer. This persistent slab remains 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 has recently been reactive with larger loads (explosives and smaller avalanches) especially in the Northern part of the region where the snowpack is thinner.

Avalanche Problems

Persistent Slabs

A very touchy surface hoar layer is buried by a 40-90 cm thick persistent slab. This layer is widespread, and is easily triggered by skiers and riders. Remote triggering with wide propagation is 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 to anything. >

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 4

Deep Persistent Slabs

The early November rain crust is buried 1-1.5 m down. It is still possible to trigger an avalanche on this interface, especially from shallow snowpack areas and thin-rocky, unsupported terrain.

Be aware of thin areas that may propogate to deeper instabilites.>Conditions may be worse in the north of the region, so get to know your local snowpack.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 3 - 6