Avalanche Forecast

Issued: Jan 6th, 2013 9:20AM

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

mpeter, Avalanche Canada

Kootenay Boundary.

The danger will begin at moderate and climb as the new snow accumulates. If you find more than 20cm of new snow, expect danger to be considerable.

Summary

Confidence

Fair - Timing of incoming weather is uncertain

Weather Forecast

Monday: Expect clouds to build with precipitation beginning in the afternoon and continuing through the evening. Up to 15-20cm are possible. Temperatures should reach -7 with light west winds.Tuesday: Flurries are possible with light accumulations and temperatures of -8. Winds stay westerly but increase through the day before easing overnight.Wednesday: Another wave of precipitation with accumulations of 15-20cm possible. Winds turn southwesterly and increase to 70km/h with temperatures reaching -8.

Avalanche Summary

Continued sluffing in steep terrain to size 1.0, otherwise no new.

Snowpack Summary

Up to 15cm of low density new snow overlies the January 4th interface. Moderate south/southwest winds have redistributed this new snow into small windslabs in immediate lee features in the alpine and exposed treeline.The January 4th interface consists predominantly of loose facets up to 30cm deep. In isolated locations (sheltered treeline and below treeline) surface hoar up to 12mm is present. There is a 1-3cm sun crust on steep south and west facing terrain. In exposed locations, old windslabs linger. The new snow is bonding poorly to this interface.The midpack is well bonded and strong. Concern remains in specific locations (Rossland Range) for the November 28 surface hoar buried 95cm. The deep crust/facet combo from early November still exists and concern remains (although unlikely) for triggering from a shallow spot.

Problems

Wind Slabs

New windslabs have formed in immediate lee and cross loaded locations.

Use ridges or ribs to avoid pockets of wind loaded snow.>Be cautious as you transition into wind affected terrain.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Loose Dry

The volume of sluffing has increased with the new storm snow. I expect this problem to evolve into a storm slab as the new snow builds; expect a more cohesive slab if you find more than 20cm of new snow.

Be cautious of sluffing in steep terrain.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Jan 7th, 2013 2:00PM