Avalanche Forecast

Issued: Dec 18th, 2015 6:02PM

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

Ruari Macfarlane, Parks Canada

Waterton Lakes.

The most consistent ski quality lies in wind-sheltered treeline terrain, where storm slabs are less prevalent. Ice climbs have begun reforming during the past week, however watch for sluffing from steep gullys above.

Summary

Weather Forecast

A weak front raced over the region today, with the freezing level around town. Light snowfall will taper off by morning. Temperatures will gradually lower Saturday, and remain cool all week. A mix of sun and cloud tomorrow, with the odd flurry in the West. Another weak front Sunday brings us blustery winds and light snowfall from midday on.

Snowpack Summary

10cm of dense new snow at treeline has fallen on top of low density fluff, or on previously visible windslabs near ridges. Light to Moderate W winds are transporting this snow to immediate lees at ridgetop. A week-old rain crust, buried 25-40cm down, is present from treeline down, and a mid-November crust down 30-60cm caps a strong lower snowpack.

Avalanche Summary

Loose dry sluffing observed out of steep terrain this afternoon.

Confidence

Due to the number of field observations

Problems

Storm Slabs

New snow and light wind transport have created storm slabs. These may entrain loose snow in their track and grow in size.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.Use caution in lee areas in the alpine and treeline. Recent storm snow has formed touchy slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Loose Dry

Watch for sluffing in gullys and couloirs.These may be triggered by wind or humans, and run fast on old crusts where they are near the surface.

The volume of sluffing could knock you over; choose your climb carefully and belay when exposed.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 1

Valid until: Dec 21st, 2015 4:00PM