Avalanche Forecast

Issued: Dec 27th, 2018 4:00PM

The alpine rating is moderate, 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.

New snow and strong winds will increase the hazard on Saturday. Ski quality is very slowly improving, but the ice is getting fatter by the day!

Summary

Weather Forecast

Friday remains cold with isolated flurries and the winds picking up to moderate from the west. On Saturday a low pressure system is moving in depositing 10cm of new snow with strong westerly winds and freezing levels rising to 1400m. This system will move out by Sunday with colder temperatures and light northerly winds.

Snowpack Summary

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

Avalanche Summary

Isolated loose dry avalanches to size 1 were observed in steep rocky terrain in the Cameron Lake area.

Confidence

Intensity of incoming weather systems is uncertain on Saturday

Problems

Wind Slabs

New windslabs will be forming with incoming precipitation and wind on Saturday, but snowfall amounts are uncertain. Keep an eye on how much snow actually arrives, these will be developing on facetted low density snow and may be easy to trigger

If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Watch for shooting cracks or stiffer feeling snow. Avoid areas that appear wind loaded.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

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 30th, 2018 4:00PM