Avalanche Forecast

Issued: Feb 22nd, 2016 6:52PM

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

jonas hoke, Parks Canada

Waterton Lakes.

Ski conditions at upper elevations have recovered dramatically since last week, don't let sunny skies and great skiing drive your decision making process.

Summary

Weather Forecast

A ridge of high pressure is building over Western Canada that is forecast to bring settled weather through the week. Skies will be mostly clear, with light and variable ridge top winds, and freezing levels remaining near valley bottom.

Snowpack Summary

10-15cm new snow near the divide Friday night created touchy storm slabs. At treeline and in the alpine this covers the previous layers of stiff windslab over a couple of buried crusts, down as deep as 55cm and 70cm (widespread below 2200m and extending into the alpine on solar aspects). Below treeline is dust on crust over a strong snowpack.

Avalanche Summary

A few natural size 1.0-2.0 storm slab avalanches have been observed and reported over the weekend. Ski cutting on Saturday and Sunday easily produced size 1.0 storm slab avalanches in sufficiently steep terrain (it's easy to imagine that these would have been up to size 1.5 in larger terrain features)

Confidence

Problems

Storm Slabs

Fresh storm slabs remained touchy through the weekend. These can be managed readily with ski cutting in appropriately non-consequential terrain, but may be large enough to be destructive in bigger terrain features.

The new snow will require several days to settle and stabilize.Avoid steep, open slopes.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

While mostly unlikely to trigger, buried layers of old windslab over a couple of buried crusts have the potential for wide propagation. Use a probe or a pole to check for the presence of these buried layers.

Carefully evaluate big terrain features by digging and testing on adjacent, safe slopes.If triggered the storm slabs may step down to deeper layers resulting in large avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1 - 3

Valid until: Feb 25th, 2016 4:00PM