Archived

Avalanche Forecast

Feb 27th, 2013–Feb 28th, 2013

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

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

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

Regions: Kananaskis.

Human triggering is still possible in steep and unsupported features. A "Pineapple Express" is forecasted for Thursday night that will bring extreme SW winds and above freezing temperatures. Watch for instabilities associated with the warming trend.

Confidence

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

Weather Forecast

A mix of sun and cloud is expected on Thursday with temperatures warming to -5 in the alpine. A strong pacific front will enter the area some time on Thursday night or Friday morning. This front will bring above freezing temperatures and extremely strong SW winds. Light precipitation is also expected. Freezing level will climb above 1900m on both Friday and Saturday.

Avalanche Summary

Nothing new today, but observations were limited.

Snowpack Summary

Soft slabs are prominent in lee and cross-loaded features at 2300m and above, and remain sensitive to human triggering in steep and unsupported features. In high alpine areas hard slabs are also prevalent. Buried wind slabs formed in late January are found 20 to 50cm deep in the alpine and high treeline areas and are still possible to trigger especially in shallow snowpack regions.

Avalanche Problems

Wind Slabs

Soft slabs at treeline and above are still sensitive to human triggering, especially in steeper lee and cross-loaded features. Alpine areas are scoured with areas of hard slab and soft slab. Increased cornice development taking place.

Be cautious as you transition into wind affected terrain.>Choose well supported terrain without convexities.>

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

Elevations: Alpine, Treeline.

Likelihood: Possible

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 20 to 50cm in the snowpack and are likely more trigger-able from shallow snowpack areas.

Avoid convexities or areas with a thin or variable snowpack.>Be aware of thin areas that may propagate to deeper instabilites.>

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

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 2 - 4