Avalanche Forecast

Issued: Dec 16th, 2016 3:00PM

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

matt.mueller, Alberta Parks

Kananaskis.

There may still be small, isolated pockets of windslab at treeline. As you approach wind effected areas anticipate a change in the feel of the snowpack.

Summary

Confidence

Moderate - Wind speed and direction is uncertain on Monday

Weather Forecast

Another day similar to today. Mostly clear skies with cold temps. Overnight we'll see about -25 as a low. The forecast says we'll get -19 as a high but the pattern suggests it will be colder. Alpine winds will be increasing and be around 40km/hr from the west. Needless to say, we will not get any snow tomorrow.

Avalanche Summary

Several loose dry avalanches were noted in extreme alpine terrain. On average they were sz 1 and did not run very far.

Snowpack Summary

Today's adventure was to Murray Moraines. This area holds cold air and tends to be a known area for a weak snowpack. Below treeline, the story is the same as always- get out of there ASAP! Treeline is where we start to see a significant change in the snowpack depth and quality. The majority of areas at treeline have a consistently thick layer of facets above the crust. The older windslabs that were everywhere earlier in the month have rotted out and become less of a problem. The exception is in areas that had seen severe windloading. Any area that had a hard slab prior ro the cold snap, tends to still have the slab intact. That hard slab appears to have acted like a barrier and increased the amount of facetting below. We encountered some VERY hollow sections today. Here's the word: variable! Every ski turn brought a different character. The alpine is similar, but expect the Nov 12 crust to fade away at about 2400m. It is likely present as a weak facet layer, but at this time the whole snowpack is weak so its hard to distinguish where exactly it is.

Problems

Wind Slabs

For the most part cold is breaking these down, the exception is in wind prone areas. Watch for a lingering hard slab as you approach wind features.

Use caution on open slopes and convex rolls Watch for areas of hard wind slab in steep alpine features.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

This exists up to 2400-2500m. Probing will help travelers nail when the crust disappears. At that point it may be worth a dig to inspect it and look for the facet layer that was once the crust.

Evaluate unsupported slopes critically.If triggered the wind slabs may step down to deeper layers resulting in large avalanches.