Avalanche Forecast

Issued: Jan 25th, 2013 8:00AM

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

catherine brown, Parks Canada

Glacier.

Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones. Choose stopping and re-grouping spots in mature forest well away from avalanche paths.

Summary

Weather Forecast

Up to 10 cm of snow is forecast for the park today, ending around noon. Expect moderate southwest winds and air temps around -5. Flurries are possible through the outlook to Sunday, with possible light amounts during the day on Sunday. Temperatures will remain seasonal.

Snowpack Summary

30 to 45 cm of new snow has covered a variety of surfaces including, small surface hoar and sun crust on steep south through west slopes. This also covers widespread wind effect in open areas at treeline and in the alpine.Moderate southerly winds have loaded northerly aspects during the storm. Below treeline the new snow is unconsolidated.

Avalanche Summary

A medium natural avalanche cycle occurred early Friday morning. Many paths along the highway corridor ran size 2-2.5, with a few running to size 3.0. Deposits were reaching the end of run outs in some events. We have few backcountry observations, but suspect similar avalanches were occurring up all the drainages.

Confidence

Due to the number of field observations

Problems

Storm Slabs

45cm of new snow has created storm slabs. These can be triggered by riders especially in steep terrain. Watch for wind effected snow on north/northeast slopes in open areas at treeline and in the alpine. Snow will be sluffing in steep treed terrain.

Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.Stay off recent wind loaded areas until the slope has had a chance to stabilize.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

A weak layer down around 80-100 cm might still be reactive to skier triggering. No natural avalanches have been observed on this layer recently. New snow overnight may overload this layer, causing it to fail with the additional weight of a rider.

Dig down to find and test weak layers before committing to a line.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Jan 26th, 2013 8:00AM