Avalanche Forecast

Issued: Dec 12th, 2012 8:09AM

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

Parks Canada sylvia forest, Parks Canada

Good skiing can be found in Glacier Park today, but be aware of wind affected areas and surprises such as pockets of slab, and early season hazards.

Summary

Weather Forecast

Overcast skies with sunny breaks are expected today, with very light precipitation and light NW winds.  More precipitation is expected on Friday, but only light amounts.  Temperatures will stay mild.

Snowpack Summary

Recent storm snow has developed into a wind slab in the alpine, and rests on a well settled mid-pack.  The Nov. 28 crust-surface hoar layer, and the Nov. 6 crust can both be found in profiles, but are not very reactive in tests.

Avalanche Summary

A few isolated natural avalanches were observed from steep terrain yesterday, mostly from north aspects.  Avalanche control produced several slab avalanches up to size 3.5.  Most of these were high elevation targets where cross loading was a factor.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Friday

Problems

Wind Slabs

An icon showing Wind Slabs
Near ridge line, steady moderate to strong winds have created pockets of wind slab, which may be easily triggered by skiers.  Cross loaded features and gullies should also be treated with caution.
The recent snow may now be hiding windslabs that were easily visible before the snow fell.Travel on ridgetops to avoid wind slabs on slopes below.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Storm Slabs

An icon showing Storm Slabs
There has been 75cm of new snow over the last 6 days at treeline.  Conditions are likely to be "heavy over light" increasing the likelihood of skier triggering.
Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.Avoid lee and cross-loaded terrain near ridge crests.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Loose Dry

An icon showing Loose Dry
With an additional 10-15cm of very light snow, sluffing is a concern where the wind has had no effect. Caution skiing in steep terrain and over terrain traps where sluffs will gain mass into avalanches.
Be cautious of sluffing in steep terrain.Early season hazards such as rocks, trees and stumps are still visible.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Dec 13th, 2012 8:00AM