Avalanche Forecast

Issued: Jan 26th, 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.

Mellow treeline terrain will be your best bet for good skiing right now. Avoid big alpine features right now.

Summary

Confidence

High -

Weather Forecast

Avalanche Summary

Some loose dry avalanches from yesterday's storm were evident as the light improved. Of note, there was one sz 2.5 slab avalanche on Mount Buller. NE aspect, 2200m. It started in the alpine on what appeared to be the Nov 26 crust. As it traveled, it pulled out the gully sidewalls and ran quite far.

Snowpack Summary

Lots of tricky layers out there at the moment. At first they seem confusing, but thinking of them from an elevation perspective helps. They are all on our radar as problems and they all have potential to produce large avalanches. Here's the run down:Alpine- We have the Dec 15th facet layer as the main trouble maker and some surface windslabs that are lingering. The 15th layer is down 80-120cm and has been responsible for several slides in the last week.Treeline- The Dec 15, Jan 6th surface hoar layer, Jan 18th surface hoar layer are all present. They are down about 85, 65 & 45cm respectively. Some avalanches have been noted on the 6th, and tests show failures on all 3 layers.Below Treeline- Basically the same as treeline, but a lack of snow load and/or a slab property above the layers prevents them from being as big a problem. The ski quality is actually quite good in mellow, treeline terrain. Alpine features have been windloaded and look plump at the moment.

Problems

Wind Slabs

This layer is widespread in the alpine and exposed treeline areas. Expect them to extend far below the ridge crests. They will likely step to deeper layers as they carry downhill.

Avoid steep lee and cross-loaded slopesBe careful with wind loaded pockets, especially near ridge crests and roll-overs.Minimize overhead exposure; avalanches may reach the end of run out zones.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1.5 - 2.5

Persistent Slabs

This persistent slab is actually a couple of persistent weak layers that we've described individually in the snowpack summary. There is a serious snowpack weakness in areas that we wouldn't normally expect.

Avoid convex rolls at and below treeline where buried surface hoar may be preserved.Carefully evaluate terrain features by digging and testing on adjacent, safe slopes.Watch for whumpfing, hollow sounds, and shooting cracks.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Valid until: Jan 27th, 2018 2:00PM