Avalanche Forecast

Issued: Jan 10th, 2015 7:44AM

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

jlammers, Avalanche Canada

South Columbia.

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

Summary

Confidence

Fair

Weather Forecast

Only trace amounts of snow are expected throughout the forecast period. Overcast conditions are forecast for Sunday, although skies should become increasingly clear on Monday and Tuesday as a dry ridge of high pressure becomes the dominant air mass. Ridgetop winds should remain generally light, while freezing levels will remain at valley bottom.

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

Recent warm temperatures have aided in the settlement of the recent storm snow resulting in 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 sensitive to human triggers with reports of remote triggering and long fracture propagations.

Problems

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

Possible - Likely

Expected Size

3 - 5

Storm Slabs

Recent accumulations have settled into a thick slab. Watch for increased sensitivity to triggering in wind-exposed terrain.

Give cornices a wide berth when travelling on or below ridges.>The new snow will require several days to settle and stabilize.>Be cautious as you transition into wind affected terrain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Jan 11th, 2015 2:00PM