Avalanche Forecast

Issued: Jan 2nd, 2014 8:29AM

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

ccampbell, Avalanche Canada

South Coast.

Summary

Confidence

Fair - Intensity of incoming weather systems is uncertain on Thursday

Weather Forecast

Friday: A mix of sun and cloud with isolated flurries possible in the morning, moderate NW winds and freezing levels dropping to 800m. Saturday and Sunday: Mostly sunny and dry with light W alpine winds and freezing levels around 900m.

Avalanche Summary

No avalanches were reported on Tuesday.

Snowpack Summary

New snow is expected to be poorly bonded, especially on wind-loaded slopes. Snowpack depths vary greatly across the region with 165cm at treeline in the Cascades but only about 65cm in the Duffey Lake area, and terrain below treeline is still mostly below threshold for avalanche activity. In general the snowpack is shallow with a faceted and weak lower half, but also highly variable. Snowpack testing on a SSE facing slope at 2000m in the Duffey Lake area on Monday produced easy to moderate, sudden collapse compression test results, and a RB3, whole block release Rutschblock result down 20cm on the mid-December surface hoar, as well as moderate sudden planar and RB1 results down 46cm on the late-November facets where they were found above a hard crust. However, these weak interfaces appear generally well bonded in the Cascades.Early season riding hazards such as rocks, stumps and logs are lurking below the surface at treeline elevations and below.

Problems

Wind Slabs

Fresh touchy wind slabs could be lurking below ridge crests and behind terrain features.

Use ridges or ribs to avoid pockets of wind loaded snow.>Be careful with wind loaded pockets near ridge crests and in terrain depressions>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Persistent Slabs

Primarily in the northern part of the region and shallow snowpack areas. Persistent weaknesses may be particularly touchy where there is an associated crust.

Use caution on open slopes and convex rolls at treeline where buried surface hoar may be preserved.>Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.>Use caution in shallow snowpack areas where triggering is more likely.>Dig down to find and test weak layers before committing to a line.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 5

Valid until: Jan 3rd, 2014 2:00PM