Archived

Avalanche Forecast

Dec 31st, 2011–Jan 1st, 2012

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

3: Considerable

The avalanche danger rating below treeline will be considerable

Regions: Glacier.

A very reactive surface hoar layer may be triggered on all slopes that have not already avalanched. Slopes must be carefully assessed and it is essential that groups minimize exposure even in the trees, where consequences are high. Fidelity HS 260

Avalanche Problems

Wind Slabs

Sustained southerly winds have loaded storm snow onto lee slopes. Expect triggerable windslabs and loaded pockets below ridgecrests and on exposed features. Yesterday, in neighbouring areas skiers triggered sz 2.5 avalanches in steep alpine terrain.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3

Persistent Slabs

A series of weak surface hoar layers (down 80 and 110cm) have been rapidly loaded. These layers are very reactive and easily triggered. Avalanches will propagate widely, may be remotely triggered, and fracture above skiers.

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 2 - 4

Deep Persistent Slabs

In the high alpine and near glacial ice the base of the snowpack is weak due to facetted crystals. Cornices are getting large and may provide the trigger needed to produce large avalanches. Glide cracks failing at ground are also a concern this year.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 3 - 4