Avalanche Forecast

Issued: Feb 15th, 2018 3:00PM

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

matt.mueller, Alberta Parks

Kananaskis.

It is still a recommendation to avoid overhead exposure. Recent avalanche activity suggests the snowpack is still fragile.

Summary

Confidence

High -

Weather Forecast

It will be cloudy overnight with temps dipping to -18C. Tomorrow, we're expecting another 6cm with wind. The average wind speed will be 25km/hr and gusts up to 50km/hr and out of the west. The temps will climb to -12C.

Avalanche Summary

Several new avalanches were noted today. Their exact age is hard to predict, but we think they occurred during yesterday's wind event. These were in very steep, unsupported treeline terrain mostly. This indicates that the snowpack is still adjusting to the new loading.

Snowpack Summary

Our heavy snowfall warning fizzled out and only left 5cm behind. For the moment, this snow remains untouched by the winds. Expect that to change as the winds pick up this evening. The alpine is widespread windslabs or exposed gravel ridges. Treeline has a widespread windslab that is stiff and poorly bonded to the layer underneath. This slab is only 5-10cm thick so it doesn't present a huge problem, unless a terrain trap is involved. A treeline profile today had the Jan 6th layer down 110cm and the dec 15 layer down 130cm. Neither layer reacted in tests at this location. This suggests the snowpack is "healing", but we'd like to look at more sites before saying the snowpack is improving.

Problems

Wind Slabs

The upper snowpack has several windslabs piled on top of each other. Yesterday's wind has left a touchy slab on the surface, or lightly buried.

Use caution in lee areas. Recent wind loading has created wind slabs.Be wary of slopes that did not previously avalanche.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1.5 - 2.5

Persistent Slabs

The surface hoar is still intact in many treeline areas. It's depth varies, but a meter down is a good generalization. We are still treating this layer with caution and respect. Surface hoar is known for unexpected surprises.

Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.Be wary of slopes that did not previously avalanche.Dig down to find and test weak layers before committing to a line.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1.5 - 2.5

Valid until: Feb 16th, 2018 2:00PM