Avalanche Forecast

Issued: Dec 7th, 2012 8:11AM

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

catherine brown, Parks Canada

Glacier.

Good skiing can be found in many areas of the park. Early season hazards are still present below 1500 m.

Summary

Weather Forecast

As a ridge of high pressure begins to move in conditions are slowly changing to cool, dry and sunny weather. 5 cm of snow is forecast for the park today with treeline temperatures around -8 deg and light NW winds. Snow will taper out tonight bringing sunny skies above possible valley cloud tomorrow with cooler temperatures and no precipitation.

Snowpack Summary

A 60cm storm slab is gaining strength. Buried WSL exists in some areas. Nov28 layer which will be most reactive where it overlies a crust on steep SW-W slopes in the alpine or where surface hoar was buried. The Nov 6 crust may become reactive with increasing load in areas where it is breaking down with mixed forms and facets present around crusts.

Avalanche Summary

Little activity observed yesterday considering 15cm HN and past high to extreme winds. No new avals were observed along the highway corridor or in the Mt. Fidelity area. Minimal sluffing observed skiing steep sheltered slopes at all elevations. A medium avalanche cycle occured on Wednesday concentrated to the steep terrain east of Rogers Pass.

Confidence

Wind effect is extremely variable

Problems

Wind Slabs

Strong S-SW winds have deposited wind packed snow on various terrain features. Buried wind slabs have been observed in the park, use your pole to feel for these as transitioning into open terrain.

Be cautious as you transition into wind affected terrain.Use ridges or ribs to avoid pockets of wind loaded snow.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 4

Storm Slabs

A weak layer down around 65 cm is starting to react less in stability tests. Rider-triggering is still possible. Use caution on steep slopes facing SW-W in the alpine where a buried thin sun crust identifies the weak layer.

Be cautious of sluffing in steep terrain.Carefully evaluate big terrain features by digging and testing on adjacent, safe slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

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