Avalanche Forecast

Issued: Jan 9th, 2015 7:35AM

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

ccampbell, Avalanche Canada

South Columbia.

Diligence may be required to maintain conservative decisions when seeking decent riding conditions over the weekend.

Summary

Confidence

Good

Weather Forecast

The forecast period is looking mostly cloudy with a chance of light flurries especially on Saturday. Freezing levels remaining in valley bottoms for the forecast period, with no more warm air expected at higher elevations. Winds should remain generally light and variable.

Avalanche Summary

Natural avalanche activity has tapered off, but storm and persistent slabs remain highly sensitive with several reports of human-triggered avalanches up to Size 2 and explosive-triggered avalanches up to Size 3. Of note were several remotely triggered avalanches involving persistent slabs showing the ability of these weaknesses to propagate into very large avalanches.

Snowpack Summary

Warm temperatures have aiding in the settlement of the recent storm snow resulting in sensitive storm slabs up to 70 cm thick. A breakable surface melt-freeze crust can be expected on all aspects below approximately 1800 m and sun-exposed slopes above. Around 80-140 cm down in the snowpack the mid-December surface hoar/crust weakness continues to be highly sensitive to human triggers with reports of remote triggering and long fracture propagations. Recent snowpack tests are producing easy sudden results down around 25 cm within the storm snow.

Problems

Storm Slabs

Heavy amounts of recent storm snow has settled into thick slabs that are highly sensitive to human triggers. Treat slopes that have yet to slide with suspicion.

The new snow will require several days to settle and stabilize.>Give cornices a wide berth when travelling on or below ridges.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 4

Persistent Slabs

A persistent weakness buried mid-December is primed for human triggers and wide propagations producing very large avalanches. Remote triggering from flat terrain and step-down from shallower weaknesses makes this problem especially tricky to manage.

Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

3 - 6

Valid until: Jan 10th, 2015 2:00PM