Archived

Avalanche Forecast

Jan 6th, 2017–Jan 7th, 2017

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

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

Regions: Banff Yoho Kootenay.

Natural activity has completely trailed off for a few days. Open areas still hold the potential for larger releases of slab over weak facets.

Weather Forecast

Cold temperatures and flurries are forecast. Two lows in the Pacific are presently doing battle with the impressive high that has dominated our weather. As of yet things are still forming but we may be looking at snow and warmer temps reaching us by Monday. Unfortunately, the snowpack is presently weak and cannot support loading.

Snowpack Summary

20-30 cm of facetting storm snow sits over top of the Dec 19 layer facet layer which in turn sits on the Nov 12 raincrust. Winds over the past week have created wind slabs in exposed areas. In many places these wind slabs sit on a weak snowpack comprised of facets and depth hoar.

Avalanche Summary

Two small loose dry avalanches were noted in Kootenay today from rocky terrain.

Confidence

Timing, track, or intensity of incoming weather system is uncertain

Avalanche Problems

Wind Slabs

Wind slabs up to 40 cm thick exist in the alpine and some treeline locations. Even a small wind slab has the potential to step down into the weak facetted mid-pack resulting in a bigger avalanche.

Be careful with wind loaded pockets while approaching and climbing ice routes.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.

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

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2

Persistent Slabs

The mid and lower pack is weak and facetted, and will remain this way for the foreseeable future. This layer is most concerning in areas where a cohesive slab overlies this weak foundation.

Watch for whumpfing, hollow sounds, and shooting cracks.

Aspects: All aspects.

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 1 - 3

Loose Dry

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

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2