Archived

Avalanche Forecast

Nov 20th, 2013–Nov 21st, 2013

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

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: Banff Yoho Kootenay.

There is lots of snow available for transport. Pay attention to local winds and be aware of fresh wind slabs.

Weather Forecast

High pressure dominates the region. Mixed sun and cloud with no snow in the forecast. Another cool day for Thursday and then a warming trend for the weekend.

Snowpack Summary

Thirty to 50 cm of low density storm snow received throughout the area in past six days. Sunshine reporting lots of reactive wind and storm slabs while north of Lake Louise wind effect not as wide-spread. The mid pack is slowly gaining a bit of strength. The Oct rain crust persists at ground level in some alpine terrain.

Avalanche Summary

From Lake Louise to Bow Summit there was evidence of a cycle up to Class 2 occurring during the storm, however surprisingly little recent natural activity. Explosive work at Sunshine produced many avalanches on N-NE aspects up to Class 3. There was wide propagation with some avalanches stepping down to the Oct crust.

Confidence

Avalanche Problems

Storm Slabs

Sunshine Village reporting a touchy storm slab that is easily triggered and has wide propagation. Some slabs have stepped down to the October rain crust layer producing avalanches up to Class 3. See avalanche reports.

Use caution in lee areas in the alpine and treeline. Recent storm snow has formed touchy slabs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 3

Wind Slabs

Thirty to 50 cm of recent storm snow and moderate winds have produced wind slabs in alpine terrain. This wind effect is more pronounced in the Sunshine area.

Be careful with wind loaded pockets while approaching and climbing ice routes.Use caution in lee areas in the alpine. Recent wind loading have created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2