Archived

Avalanche Forecast

Dec 5th, 2011–Dec 6th, 2011

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Glacier.

Large areas of Glacier National Park are CLOSED for avalanche control using EXPLOSIVES. Daily or annual winter permits are required to access winter restricted areas. Access information is available at the Rogers Pass Discovery Centre.

Avalanche Problems

Loose Dry

Point releases of low density storm snow are the only avalanches observed in the past few days. These are occurring on steep slopes and triggered by tree bombs or snow falling from cliffs.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible

Expected Size: 1 - 2

Deep Persistent Slabs

A persistent weak layer near the ground is responsible for isolated but very large avalanches. This needs a large trigger or may be easily triggered from shallow areas.

Aspects: All aspects.

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 4

Wind Slabs

Wind transported snow has formed slabs in exposed terrain above treeline on most aspects as wind direction has been variable over the past three days.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2