Avalanche Forecast

Issued: Dec 28th, 2014 3:00PM

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

pgoddard, Avalanche Canada

Northwest Inland.

Watch for wind slabs lurking in unusual places as the winds have been shifting direction.

Summary

Confidence

Poor - Due to the number of field observations

Weather Forecast

Cold and dry with strong N-E outflow winds. A temperature inversion may form on Wednesday.

Avalanche Summary

A naturally-triggered size 2 slab was observed on Saturday on an alpine NE aspect in steep, windloaded terrain. A naturally-triggered size 1.5 wind slab was also observed at treeline on a north aspect in the Hankin area, which probably failed on Wednesday or Thursday. On Tuesday we received a report of a size 1.5 skier remotely triggered avalanche in the far north of the region. It released on a steep, wind loaded feature and was triggered from 5m away. The 25-45 cm thick slab occurred around 1600 m elevation.

Snowpack Summary

10-20 cm new snow from Friday night is likely to form new wind slabs on south to west-facing slopes as winds shift into an outflow pattern. Older wind slabs from previous westerly winds are buried underneath. A layer of buried surface hoar down about 30-50 cm appears to be spotty in distribution, but may still be a concern in some areas. Near the base of the snowpack, the mid-November crust-facet layer has become less likely to trigger, but is still in the back of our minds.

Problems

Wind Slabs

Winds are expected to shift recent snow into slabs behind terrain breaks like ridges and ribs.

Travel on ridgetops to avoid wind slabs on slopes below.>Be alert to wind slab conditions, which may be found on a variety of slope aspects. Wind slabs may look smooth, bulbous or fat. >

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Dec 29th, 2014 2:00PM