Archived

Avalanche Forecast

Dec 31st, 2012–Jan 1st, 2013

Alpine

1: Low

The avalanche danger rating in the alpine will be low

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

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: Banff Yoho Kootenay.

Warming temps on Wed and Thurs will increase the danger from loose snow avalanches on steep solar aspects.

Weather Forecast

An upper ridge continues to bring clear skies and light winds with no precip for the forecast period. Daytime temperatures will warm throughout the week with alpine highs approaching zero on wednesday and thursday.

Snowpack Summary

20-40cm thick wind slabs exist in high alpine features and are stubborn to unreactive from field reports. W of the divide, a well settled snowpack exists in deeper locations with the basal Nov 6 crust well bonded. In the front ranges E of the divide, a facetted snowpack exists with the Nov 6 basal crust being mainly facetted.

Avalanche Summary

Yesterday, a guide reported evidence of a fresh loose dry avalanche on the ice climb 'Rogans Gully' on Cascade mountain. Be wary of loose dry avalanches in steep terrain as the snowpack continues to facet. Otherwise no new avalanches observed.

Confidence

The weather pattern is stable

Avalanche Problems

Wind Slabs

Reports are showing windslabs created in the last week are stubborn to unreactive on lee ridgetop features. Most likely triggerable in aggressive, steep, lee terrain near ridgetops.

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

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2

Loose Dry

This problem exists mainly in thin snowpack areas E of the divide where the snowpack has completely facetted and lost all cohesion. Watch for sloughing in steep terrain where the snow is unsupportive.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible

Expected Size: 1 - 2

Cornices

The cold temperatures are facetting out cornices and large cornice failures have been observed. Although the cornice failures have not been triggering slabs on the slopes below, the cornice chunks themselves would definitely hurt if they hit you

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 2