Archived

Avalanche Forecast

Mar 18th, 2012–Mar 19th, 2012

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

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

2: Moderate

The avalanche danger rating below treeline will be moderate

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: Kananaskis.

Conditions are improving but there are still lots of places backcountry users can get into trouble. Most accidents happen immediately following a storm when the weather improves. Conservative decision making and careful snowpack evaluation is key.

Confidence

Good

Weather Forecast

No new snow is in the forecast for the next 48hrs. Winds were continue to be light out of the SW with temperatures being seasonal with daytime highs at treeline around -8C.

Avalanche Summary

Sluffing up to size 1 out of steep unskiable terrain throughout the forecast area. No new slab activity was observed.

Snowpack Summary

Upper snowpack continues to settle. Easy to Moderate sheers persist within the storm snow but they are strengthening. On solar aspects the March 11th temperature crust down 40-50cm is producing easy to moderate sheers. The valentines day surface hoar layer is now buried 140-170cm and is becoming more stubborn to trigger.

Avalanche Problems

Storm Slabs

Light to moderate winds have created storm slabs up to 40cm thick along ridgelines and in crossloaded features at treeline and above. Avalanches starting in the upper snowpack will likely step down to one of the deeper problem layers.

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

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 4

Persistent Slabs

Surface hoar buried up to 160cm continues to be a major concern in the snowpack. A dense slab now sits on top of this layer. Avalanches in the upper snowpack will likely step down to this layer causing a destructive avalanche.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 2 - 6

Persistent Slabs

The March 11th Temperature crust is buried down 50cm on solar aspects. The bond of the upper snowpack to this crust is highly variable and requires careful evaluation as you travel.

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 4

Cornices

Cornices have grown significantly in the alpine. Failures continue to occur and have triggered avalanches up to size 3 on the underlying slopes. Give cornices a wide berth and stay well back from corniced ridge crests.

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 2 - 7

Deep Persistent Slabs

The weak basal facets and depth hoar have re-awakened. Large terrain features are areas of concern where a smaller slide could step down and trigger a very large avalanche with deep and wide propagation.

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

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 3 - 7