Avalanche Forecast

Issued: Feb 17th, 2017 3:28PM

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

mike.koppang, Alberta Parks

Kananaskis.

Warm temps are helping to strengthen the snowpack at the lower elevations but treeline and alpine we still have a concern from natural and human triggered avalanches.

Summary

Confidence

High - Timing or intensity of solar radiation is uncertain on Saturday

Weather Forecast

Temperatures will remain seasonal on Saturday with daytime highs around -5 at 2500m (treeline).Â 5-10cm of new snow is forecast to fall and winds will be light to moderate out of the SW.Â Freezing levels will be around 1800m.

Avalanche Summary

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

Snowpack Summary

5-15cm of recent snow is now overlying a widespread temperature crust at lower elevations (up to 2000m) and likely up to 2400m on pure solar aspects. As you climb into the alpine this new snow has been blown into thin (20-30cm) thick storm slabs.Â Field tests on Friday were showing these storm slabs to be unreactive to ski cutting but we werent willing to expose ourselves to larger slopes due to the weak faceteted basal layers down 100-120cm.Â Warm temps are helping to settle out the snowpack and strengthen it but this process takes time.Â We still have very little confidence in the stability of any large terrain feature and are continuing to limit our exposure to overhead terrain.Â Good skiing was being found in sheltered areas at TL and below.Â Field teams were not in alpine areas.

Problems

Storm Slabs

New storm slabs are building in alpine areas.

Avoid steep convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

Alpine and treeline areas may 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.Be aware of the potential for wide propagations due to the presence of hard windslabs.Watch for areas of hard wind slab in steep alpine features.

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 18th, 2017 2:00PM