Avalanche Forecast

Issued: Feb 19th, 2017 3:09PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Wind Slabs, Persistent Slabs and Deep Persistent Slabs.

michael.olsthoorn, Alberta Parks

Kananaskis.

Travel is much better below treeline. Exposure to large overhead hazards still a concern because of a weak faceted basal snow pack.

Summary

Confidence

Weather Forecast

Temperatures on Monday will be about -9c in the Alpine. Winds are expected to be light to moderate out of the SW with only a trace of snow forecast. Freezing level is supposed o be 1500m.

Avalanche Summary

No new natural avalanche activity was observed over the past 24hrs.

Snowpack Summary

An average of 10-20cm of recent snow is now overlying a widespread temperature crust up to 2000m and up to 2400m on solar aspects. In the Alpine, you can find thin storm slabs(up to 30cm thick). Just below this temperature crust, there is a well settled upper snowpack still sitting on a weak faceted basal layer (down approx. 100-120cm). This weak basal layer is still giving the forecasters little confidence in exposing ourselves to large terrain overhead. Good skiing was found in open areas at treeline and below.

Problems

Wind Slabs

New wind slabs 20-30cm thick in alpine areas.

Avoid lee and cross-loaded terrain near ridge crests.Avoid steep convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

Alpine and treeline areas have a sun crust on steep solar aspects up to 2400m. The deeper layers were insulated from the warmth and remain the same as they were before. Inspect this interface for signs of weakness.

Use caution in lee areas. Recent wind loading have created wind slabs.Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Deep Persistent Slabs

Past avalanches have stepped to this layer. Thin areas and transitional terrain remain a concern.

Avoid steep convexities or areas with a thin or variable snowpack.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Feb 20th, 2017 2:00PM