Archived

Avalanche Forecast

Feb 11th, 2012–Feb 12th, 2012

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

1: Low

The avalanche danger rating at treeline will be low

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

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Northwest Coastal.

Confidence

Good - -1

Weather Forecast

Saturday night: light precipitation with 5-10 mm expected. Freezing level around 700 m. Strong southwesterly winds. Sunday: Winds veering to moderate northwesterly. Lingering flurries in the morning, later becoming dry as a high pressure ridge builds. Freezing level around 700 m. Monday: Dry and sunny. Light winds. Freezing level at valley bottom. Tuesday: another weak frontal system will bring light precipitation and moderate southwesterly winds.

Avalanche Summary

No recent avalanches have been reported from this region.

Snowpack Summary

Approximately 5 cm of new snow at treeline and above has buried a surface hoar layer (crystal size reported to be 1-4 mm) lying on old surfaces comprising crusts and variable wind slabs. The crusts formed in response to successive melt-freeze cycles and are harder and thicker the lower in elevation you go. The wind slabs were deposited on a variety of aspects and are becoming increasingly stubborn and difficult to trigger. Deeper within the snowpack, a facet layer buried around Jan 20th is the greatest concern. This layer lies approximately 110-140 cm below the surface and still exhibits hard, sudden planar results in isolated snowpack tests.

Avalanche Problems

Cornices

Large cornices are looming over some slopes which could act as a trigger for large, deep avalanches if they collapse.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 3 - 6

Wind Slabs

Wind slabs are forming behind ridge lines in response to new snow and southwesterly winds.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 3