Archived

Avalanche Forecast

Feb 24th, 2013–Feb 25th, 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

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

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

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Kananaskis.

Above 2300m recent wind slabs are sensitive to human triggering. With another 10 to 15cm of new snow in the next 24hrs with strong SW winds, the danger level is pushing into the "upper end" of CONSIDERABLE. Keep an eye on localized conditions.

Confidence

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

Weather Forecast

10 to 15cm of new snow are possible in the next 24hrs. Winds will remain strong to moderate out of the SW. Temperatures will range from -10 to -16 on the alpine on Monday.

Avalanche Summary

Nothing new.

Snowpack Summary

Soft slabs are prominent at treeline and are increasing in stiffness, indicating a higher likelihood of human triggering. In the alpine hard slabs are widespread with pockets of soft slab in lee and cross-loaded gully features. Extensive wind transport was occurring at upper altitudes due to strong SW winds. Snowpack tests today at treeline indicate a weakness down 35cm that failed in the easy range. Another shear also appeared down 80cm, but this was in the hard range. Below 2100m the snowpack is very weak and facetted.

Avalanche Problems

Wind Slabs

Soft slabs are prominent at treeline and have become more sensitive to human triggering in the past 24hrs, especially in lee and cross-loaded features just below ridgeline. Alpine areas are scoured with areas of hard slab and soft slab.

Be cautious as you transition into wind affected terrain.>Avoid lee and cross-loaded terrain near ridge crests.>Choose conservative lines and watch for clues of instability.>

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 2 - 5

Persistent Slabs

Buried wind slabs (originally formed in late January) are still are concern in steep features in the alpine and at treeline. These slabs are found down 30 to 60cm in the snowpack and are likely more trigger-able from shallow snowpack areas.

Avoid convexities or areas with a thin or variable snowpack.>Avoid shallow snowpack areas where triggering is more likely.>

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

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 2 - 4