Archived

Avalanche Forecast

Dec 19th, 2013–Dec 20th, 2013

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

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

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

Regions: Banff Yoho Kootenay.

Basal weaknesses are waking up with the added new snow land wind loading. Avalanche control today again produced large, destructive avalanches. Use caution in avalanche terrain!

Weather Forecast

Increasing wind and moderately cold temperatures forecast for tomorrow will continue snow transport. Occasional light flurries are not expected to affect the forecast.

Snowpack Summary

Faceting and windslabs still dominate the Rockies' snowpack. The deep persistent weak layers are still reactive with additional wind-loading. Triggering overlying slabs is likely and will result in large, destructive avalanches as seen in avalanche control work today.

Avalanche Summary

Lee slopes with an easterly component are deep enough to produce large avalanches. Windslabs over loose facets may be very touchy still. All aspects are producing shallow releases which may run quickly in gullied terrain.

Confidence

Avalanche Problems

Wind Slabs

Continuing winds acting on loose facets and the remaining storm snow are expected to maintain considerable hazard in the short term.

Avoid lee and cross-loaded terrain near ridge crests.Avoid shallow snowpack areas where triggering is more likely.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3

Loose Dry

Loose snow can quickly pick up speed and mass in gullied terrain.

Be cautious as you transition into wind affected terrain.Early season hazards such as rocks, trees and stumps are still visible.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2