Archived

Avalanche Forecast

Feb 11th, 2014–Feb 12th, 2014

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

4: High

The avalanche danger rating in the alpine will be high

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

3: Considerable

The avalanche danger rating below treeline will be considerable

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

3: Considerable

The avalanche danger rating below treeline will be considerable

Regions: Kananaskis.

Danger levels are rising as a significant storm moves into the area overnight. Strong westerly winds will continue to build storm slabs through the day on Wednesday. Cautious route selection is strongly recommended.

Confidence

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

Weather Forecast

The weather forecast is uncertain, but the region could see between 15 and 20cm of new snow by the end of Wednesday with a further 15cm on Thursday. Temperatures for Wednesday should reach -7C and winds will be strong to extreme from the West.

Avalanche Summary

Isolated natural activity (both loose dry and storm slabs) was observed in steep Alpine terrain on N and E aspects up to size 1.0.

Snowpack Summary

Highly variable new snow amounts (2 to 4cm in valley bottom, 10 to 15cm at Treeline) overlie a wide variety of previous surfaces which include sun crust, surface hoar, facets, wind slab and bare ground. Storm slabs are forming in the Alpine and open areas at Treeline. The mid pack remains strong in most areas and the basal facets persist.

Avalanche Problems

Storm Slabs

Storm slabs are developing on lee aspects. While these slabs are not yet very deep, Wednesday's storm will continue to add to the load. These storm slabs will become increasingly sensitive to human triggering as the day goes on.

Avoid avalanche terrain during periods of heavy loading from new snow and wind.>Avoid steep lee and cross-loaded features>Avoid freshly wind loaded features.>

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 3

Loose Dry

Rapid snow loading will lead to sluffing in steep terrain.

Be cautious of sluffing in steep terrain.>Avoid ice climbs that are in terrain traps below large start zones.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2

Deep Persistent Slabs

The basal weakness remains, and incoming snow and wind may lead to a re-awakening of this problem. Large terrain features should be avoided.

Carefully evaluate and use caution around thin snowpack areas.>Be aware of the potential for full depth avalanches due to deeply buried weak layers.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 5