Archived

Avalanche Forecast

Mar 12th, 2013–Mar 13th, 2013

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

4: High

The avalanche danger rating at treeline will be high

Below Treeline

3: Considerable

The avalanche danger rating below treeline will be considerable

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

Regions: Kananaskis.

15cm of snow (rain at lower elevations) is possible Wednesday with extreme winds. A further 25 to 30cm are expected Thursday. As we transition to a period of higher danger levels, conservative route choices are in order.

Confidence

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

Weather Forecast

Freezing levels will rise to 1900m on Wednesday and over 2000m on Thursday as a warm storm front moves into the region. Winds are expected to be sustained at over 100km/h for the next couple of days. Wednesday could see upwards of 15cm of new snow with a further 25 to 30cm on Thursday.

Avalanche Summary

Nothing new observed today.

Snowpack Summary

Sun crusts are present on solar aspects up to at least 2400m. Snowpack remains weak and facetted at lower elevations. At alpine and treeline elevations soft slabs and hard slabs are widespread and are found on all aspects. These slabs vary significantly in their sensitivity to triggers, with one size 2.0 slab triggered by solar radiation on a south aspect yesterday .

Avalanche Problems

Storm Slabs

With the forecasted snow and wind, storm slab development will add to the extensive soft slabs and hard slabs present in alpine and treeline areas. Natural avalanche activity is expected to increase over the next 2 days.

Be cautious as you transition into wind affected terrain.>Avoid lee and cross-loaded terrain near ridge crests.>

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

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 2 - 5

Persistent Slabs

Buried slabs (formed in February) are still reactive in isolated areas. Steep lee and cross-loaded features are the primary concern. New loading on Wed and Thurs will increase the possibility of triggering this layer.

Be aware of the potential for full depth avalanches due to deeply buried weak layers.>Avoid lee and cross-loaded terrain near ridge crests.>

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 5