Avalanche Forecast

Issued: Dec 24th, 2018 4:00PM

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

adam greenberg, Parks Canada

Waterton Lakes.

Happy Holidays! Ski quality is slowly improving along the divide, but persistent weak layers remain deep in the snowpack.

Summary

Weather Forecast

We are entering a fairly benign weather pattern, with alpine temperatures remaining in the negative teens. We may see increasing cloudiness, moderate westerly winds and some flurries on Boxing day.

Snowpack Summary

The snowpack remains variable with depths ranging from 20 to 160cm along the divide. 10cm of blower sits on a variety of wind affected surfaces including wind slabs from the previous storm. The lower snowpack appears to be gaining strength in deeper areas, though thin areas remain weak.

Avalanche Summary

Isolated loose dry avalanches were observed in steep north facing alpine terrain near Cameron Lake. Our neighbours continue to see explosives triggering wind slabs to size 2

Confidence

Due to the number of field observations

Problems

Wind Slabs

Wind slabs may be sitting on a weak facet layer in some areas. Carefully evaluate the snowpack as you transition into treeline and alpine terrain.

If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Caution in lee and cross-loaded terrain near ridge crests.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

Though we have not been seeing many recent results on this layer, the potential to trigger it remains in thin snowpack areas

Caution around convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3

Valid until: Dec 27th, 2018 4:00PM