Archived

Avalanche Forecast

Feb 11th, 2017–Feb 12th, 2017

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

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

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: Kananaskis.

Choose very conservative terrain and avoid overhead exposure to avalanche slopes. Anticipate quick changes within the snowpack as the temps rise.

Confidence

High -

Weather Forecast

Over the next few days we are expecting the temps to rise significantly. At the moment, Monday will see the freezing level hit 2000m. Tomorrow's high will be -6 with cloudy skies. Winds will be around 45km/hr at ridgetop.

Avalanche Summary

Natural activity has tapered. Most fracture lines from yesterday have blown in and become reloaded. Some cornice triggered avalanches were noted in the alpine today. All were on sun exposed slopes.

Snowpack Summary

10cm of new snow from yesterday and overnight. In the alpine, this new snow was picked up by the strong winds and redistributed as more windslab. The alpine is starting to look like its old self. Lots of bare ridges and crossloaded gullies or cornices. As can be expected, the wind has helped the cornices grow. In some cases these have fallen off and started avalanches within the new windslabs. Treeline is similar to yesterday, only the wind loading and cross loading is more pronounced. With the strong winds, the alpine/treeline borders are a bit blurry right now. The alpine windslab problem will be encountered at treeline elevations. Expect windslabs everywhere to be much harder than previous days. Below treeline still has a distinct "upside down" feel to it due to the weak mid-pack. Whumphing is still common and can propagate a long ways through the weaker layers. Think of this as you approach overhead terrain.

Avalanche Problems

Wind Slabs

This is a broad category right now. Expect settlement slabs down low, and windslabs at treeline and above. The slabs are 50-60cm thick and are sitting on a variety of surfaces. Windy areas have a hardslab and sheltered areas have the Dec 18 facets.

Avoid freshly wind loaded features.Avoid cross loaded slopes at or above treeline.

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

Elevations: All elevations.

Likelihood: Very Likely

Expected Size: 2 - 3

Cornices

Cornices are large and relatively new to the scene. Expect them to fail easily, especially as it warms up.

Pay attention to overhead hazards like cornices which could easily trigger deep slabs.Give cornices a wide berth when travelling on or below ridges.

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

Elevations: Alpine.

Likelihood: Very Likely

Expected Size: 1 - 3

Deep Persistent Slabs

Many avalanches have stepped to this layer. Very large avalanches can be expected if this layer is involved. Large triggers(cornices) may wake this layer up.

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 4