Avalanche Forecast

Issued: Jan 11th, 2017 4:47PM

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.

jlammers, Avalanche Canada

Cariboos.

Wind effect will drive the avalanche danger in many areas. The safest, and best, riding may be in lower elevation terrain sheltered from the wind.

Summary

Confidence

Moderate - Wind effect is extremely variable

Weather Forecast

Thursday: Clear skies / Strong westerly winds / -13 in the alpineFriday: Clear skies / Strong westerly winds / -16 in the alpineSaturday: Increased cloud / Moderate southwest winds / -11 in the alpine

Avalanche Summary

On Tuesday, numerous naturally triggered wind slabs to size 1.5 were noted in steep, high elevation terrain. Continued strong winds on Thursday should promote ongoing wind slab activity. Although natural avalanche activity will likely taper-off in the coming days, fresh wind slabs will be slower to gain strength with the cooler temperatures, and human triggering will remain a concern in wind-exposed terrain.

Snowpack Summary

Up to 36 cm of low density snow fell on Sunday night and Monday. In some areas, moderate to strong southwest and more recent northerly winds have shifted these accumulations into wind slabs at treeline and above. In deeper snowpack parts of the region, the mid-December facet layer lies up to 120cm below the surface. In these areas professionals feel this layer has generally gained considerable strength. That said, I'd carefully investigate this interface before pushing into steeper terrain, especially in shallower snowpack areas where this weakness may show prolonged reactivity.

Problems

Wind Slabs

In many areas new snow on Monday was shifted by southwest winds into reactive wind slabs in exposed high elevation terrain. A more recent switch to northerly winds has promoted a reverse loading pattern, and wind slabs may exist on all aspects.

Be cautious as you transition into wind affected terrain.Avoid areas where the snow feels stiff or slabby.Be alert to conditions that change with aspect and elevation.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

This layer has gained strength in many areas, but triggering an avalanche on facets buried in mid-December may still be possible in shallow snowpack parts of the region. Dig down and test for weaknesses before committing to larger terrain features.

Carefully evaluate big terrain features by digging and testing on adjacent, safe slopes.Avoid shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Jan 12th, 2017 2:00PM