Avalanche Forecast

Issued: Jan 7th, 2013 8:19AM

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

ali haeri, Parks Canada

Glacier.

Additional overnight snow load with wind has continued to build a more cohesive slab over weak layers.

Summary

Weather Forecast

Westerly flow will produce light to moderate precipitation today ahead of a low pressure system developing over the Pacific. This system is forecast to arrive to the interior region Tuesday night bringing moderate to heavy amounts.

Snowpack Summary

30cm of new snow over a facetted interface. This storm snow sits on a sun crust on steep south and west aspects. The Dec 25 surface hoar layer is down 40cm and the Jan 4 surface hoar layer is down around 25cm. These layers are more prominent between 1500 and 2000m. Well settled mid pack. Nov 6 crust is down 130 - 150cm.

Avalanche Summary

A natural avalanche cycle yesterday producing several avalanches to size 2.5 and two to size 3.0 throughout the highway corridor."Frequent Flyer" in the Connaught drainage had also run yesterday, size 2.0 , just reaching the up track.

Confidence

Intensity of incoming weather systems is uncertain

Problems

Storm Slabs

33 cm of new snow sits over variable weak layers such as surface hoar, sun crust or facets, depending on your aspect and elevation. These are ideal layers for an avalanche to release on.

Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

2 - 3

Wind Slabs

Steady overnight winds have created wind slabs in wind exposed areas and will react easily to skier triggering.

Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

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