Archived

Avalanche Forecast

Dec 28th, 2013–Dec 29th, 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.

The only thing certain about the snowpack right now, is how unpredictable it is.

Weather Forecast

The NW flow continues to run down through the forecast region keeping temperatures cool with bursts of snowfall and gusty winds as systems embedded in this flow pass through the area. Trace amounts of snow are expected for Sunday; then another 5 cm for Monday.

Snowpack Summary

10-20 cm of soft surface snow has formed thin windslabs in some areas, and sits on top of a shallow and weak snowpack. West of the Continental Divide the snowpack is stronger, but failures near the ground are still likely. This condition will persist until the passage of time and deeper snow can work to strengthen the lower half of the snowpack.

Avalanche Summary

There is a pattern emerging in the Lake Louise area where the snowpack is the shallowest. Steep gullies in alpine areas are producing 100cm deep avalanches to ground (up to size 2), with triggering occurring from thin spots where the snowpack is weakest. A ride in these full-depth avalanches would cause serious injury getting raked over the rocks.

Confidence

Avalanche Problems

Deep Persistent Slabs

This problem is classic. Hard to trigger, but when you hit the sweet spot (which you cannot see), full depth avalanches are likely. Don't ski aggressive terrain, the consequences are high so mange your exposure to starting zones very carefully.

Be aware of the potential for full depth avalanches due to deeply buried weak layers.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 2 - 3

Wind Slabs

10-20 cm of light new snow has fallen in the last 48-hours, and has been blown into thin windslabs in some areas. Check for windslabs and avoid freshly loaded areas. Ice climbers should watch out in steep cliffy terrain.

Be careful with wind loaded pockets while approaching and climbing ice routes.Avoid freshly wind loaded features.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2