Avalanche Forecast

Issued: Dec 29th, 2012 9:26AM

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

Avalanche Canada swerner, Avalanche Canada

Summary

Confidence

Good

Weather Forecast

The region will be dominated by a ridge of high pressure that is positioning itself over the BC coast before making its way into the Interior regions. Light north/northwesterly winds, cooler temperatures, dry and fairly clear conditions will prevail. Sunday/Monday: Alpine temperatures near -4 with ridgetop winds light from the Northwest. Freezing levels near 800 m.Tuesday: Forecast shows the possibility of thick valley clouds forming over the Kootenays, ridgetop winds light from the Northwest and sunny alpine skies. Alpine temperatures near -9, and freezing levels at valley bottom.

Avalanche Summary

An avalanche control mission done using explosives on steep 50 degree NE aspects showed minor sluffing.On December 24th Record Mt. had a natural size 2 slab avalanche that failed on the late November surface hoar layer buried down 115 cm. The avalanche occurred on a East aspect around 1900 m. Reports from the Rossland area suggest that the buried surface hoar is well preserved and the crystals are 10 mm in size. I suggest keeping this on your radar, it may be more suspectable to rider triggers in the Rossland Range.

Snowpack Summary

Last week's storm snow is settling and showing no significant shears in the top meter of the snowpack. Wind slabs have formed and may easy to trigger in specific locations, like leeward slopes, and behind terrain features (spines, gullies).Through the region, people continue to monitor the late November buried surface hoar found down 115-130 cm. Snowpack testing has shown Compression and Deep Tap test results in the hard to very hard range with a variety of fracture characteristics, including no results, breaks and some with sudden results. This layer may be difficult to trigger, but if triggered you can expect a consequential avalanche to occur. Dig down, find and test weak layers that may exist in your neck of the woods. The mid-pack is generally well settled.

Problems

Wind Slabs

An icon showing Wind Slabs
Blowing winds from variable directions has redistributed recent storm snow on North-South aspects. Use extra caution on lee slopes, behind spines, and in wind exposed areas.
Be cautious as you transition into wind affected terrain.>Use ridges or ribs to avoid pockets of wind loaded snow.>Carefully evaluate big terrain features by digging and testing on adjacent, safe slopes.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Dec 30th, 2012 2:00PM