Avalanche Forecast

Issued: Dec 25th, 2012 3:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs and Deep Persistent Slabs.

pgoddard, Avalanche Canada

Northwest Inland.

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain on Thursday

Weather Forecast

Wednesday: Light SW winds. Alpine temp -8. A few cm snow.Thursday: Light SW winds. Alpine temp -7. Light snow.Friday: Moderate to strong SW winds. Alpine temp around -5. Light snow.

Avalanche Summary

A size 2 glide slab released on an east aspect during the weekend. No other recent avalanches have been reported.

Snowpack Summary

A shallow snowpack (about 1m deep) exists, with facets continuing to develop while arctic cold air prevails. Strong winds have scoured some SE aspects in the alpine to ground. Wind slabs exist in many wind-exposed areas, however their distribution is quite variable. Below treeline, very loose cold snow is sluffing easily from steep terrain. Professionals are still mindful of a facet/crust layer near the base of the snowpack. Although triggering it has become unlikely, it may be possible from a thin-spot trigger point or with a very heavy load (e.g. cornice fall).

Problems

Wind Slabs

Watch for wind slabs behind ridges and terrain breaks. These could be triggered by the weight of a person or snowmobile.

Be cautious as you transition into wind affected terrain.>Use ridges or ribs to avoid pockets of wind loaded snow.>Be aware of the potential for wide propagations due to the presence of hard windslabs.>

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

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 4

Deep Persistent Slabs

A deeply buried facet/crust weakness exists near the base of the snowpack. This layer could be triggered by large loads such as a cornice collapse or from a thin-spot trigger point.

Choose the deepest and strongest snowpack areas on your run.>Be aware of thin areas that may propagate to deeper instabilites.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 5

Valid until: Dec 26th, 2012 2:00PM