Avalanche Forecast

Issued: Dec 15th, 2015 8:36AM

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

esharp, Avalanche Canada

Cariboos.

Large human triggered avalanches remain possible. Start with small test slopes and build up slowly to the bigger terrain features. There is still a lot of uncertainty associated with this early winter snowpack.

Summary

Confidence

Moderate

Weather Forecast

Fairly benign weather is forecast through the forecast period. WEDNESDAY: 2-5cm, light northwest winds, -10 at 1500m. THURSDAY: 2-10cm of snow, light to moderate southeast winds, -10 at 1500m, FRIDAY: Flurries, light west winds, -10 at 1500m.

Avalanche Summary

Avalanche activity appears to have tapered off since the weekend. Avalanche professionals are reporting sluffing in steep terrain and in response to ski cutting.

Snowpack Summary

Another 5-15 cm of new snow fell in the Cariboos on Monday. There is apparently minimal wind effect in the alpine. In some places a thin crust can be found down about 20 to 45cm on all aspects as high as 1800m. Below this, down 80 to 130cm, the early December persistent weak layer is lurking. This layer can be found as a crust on solar aspects in the alpine and at tree-line. Below tree-line it has been showing up as isolated pockets of large surface hoar and/or small facets especially between 1400 and 1800m. Snow pit tests on this interface have been widely variable producing sudden planar, resistant planar and sudden collapse results. The mid and lower portions of the snowpack are thought to be well settled.

Problems

Wind Slabs

The storm slab problem should be settling out quickly, but I would still be wary of steep unsupported features, slopes immediately lee of ridge crest and convexities.

Avoid freshly wind loaded features and use ridges or ribs to sneak around these problem areas.> Start with simple terrain and take a curious/experimental approach to the snowpack. You may be able to step out into challenging and even complex terrain after learning more about the snowpack.>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 4

Persistent Slabs

A layer of buried surface hoar can be found below tree-line between 1400m and 1800m. Test profiles suggest this interface varies widely in reactivity indicating that it may still be sensitive to human triggering.

Avoid open slopes, convex rolls, burns, cutblocks and terrain traps when traveling below treeline. This is where buried surface hoar is best preserved and most volatile.>

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Dec 16th, 2015 2:00PM