Avalanche Forecast

Issued: Dec 23rd, 2012 9:14AM

The alpine rating is considerable, 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.

We have limited observations from the region. Send us yours! forecaster@avalanche.ca

Summary

Confidence

Poor - Due to limited field observations

Weather Forecast

Monday: Light S winds, with moderate to strong NE outflow winds in places. Alpine temperatures around -14 with an inversion (colder temperatures in the valley floor). No precipitation.Tuesday: Light winds. Alpine temperature around -10 with an inversion. No precipitation.Wednesday: Light SE winds. Alpine temperature around -10. No precipitation.

Avalanche Summary

No recent avalanches have been reported.

Snowpack Summary

Wind slabs and cornices are likely to have developed on a fairly widespread basis and may be found in unusual locations lee to NE and E outflow winds. Spotty surface hoar was buried in the upper snowpack in sheltered treeline areas, although little is known about its reactivity. Near the base of the snowpack, a facet/crust layer remains a concern for unlikely but possible deep releases. It may be possible to trigger this weakness with a very heavy load (e.g. cornice fall) or from a thin-spot trigger point.

Problems

Wind Slabs

It is likely that wind slabs have developed behind ridges and terrain breaks.

Avoid travelling in areas that have been reverse loaded by winds.>Stay well to the windward side of corniced ridges.>Use ridges or ribs to avoid pockets of wind loaded snow.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Deep Persistent Slabs

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

Avoid thin, rocky or sparsely-treed slopes.>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 24th, 2012 2:00PM