Avalanche Forecast

Issued: Feb 22nd, 2014 9:01AM

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

swerner, Avalanche Canada

Kootenay Boundary.

Don't get powder hungry and let the improving weather lure you into high risk scenarios. Check out this recent remote triggered size 3 from the Kootenay Boundary.

Summary

Confidence

Fair - Timing or intensity of solar radiation is uncertain on Sunday

Weather Forecast

The arctic high off the north coast will continue pushing southward into central BC and bring a cooler, dryer NW flow to the region. Some unstable disturbances are embedded in this flow, bringing scattered cloud and light precipitation on Sunday.Tonight/ Sunday: Cloudy with sunny periods and isolated flurries. Alpine temperatures near -13.0. Light NE ridgetop winds.Monday: Sunny with some cloud. Alpine temperatures near -10.0. Ridgetop winds light from the North.Tuesday: Sunny. Alpine temperatures near -6.0. Ridgetop winds blowing light from the north and freezing levels rising to 800 m.

Avalanche Summary

Natural avalanche activity has begun to taper off; however, we are still receiving several reports of activity up to size 2.5. Explosive control and skier triggering continue to produce significantly large-very-large avalanches up to size 3. Remote triggering and long fracture propagations are occurring on all aspects and elevations. Endless settlements and whumphing experienced while traveling, even on low angle terrain. With forecast sun, the avalanche hazard may increase on solar slopes.Check out the Forcaster Blog! It shows a photo of a remote triggered size 3 from Friday in the southern part of the Kootenay-Boundary.

Snowpack Summary

Moderate SW winds have loaded leeward and cross-loaded exposed slopes. Changing winds from the north may build fresh wind slabs on southerly slopes. There is over a metre of recent storm snow that is sitting on a weak layer that is a mixture of facets, surface hoar, melt-freeze crusts and any combination of these. The weak layer is widespread at all elevations and aspects and continued whumpfing and avalanche activity is reported. The storm slab continues to settle and become more cohesive allowing for longer fracture propagations and remote triggering from up to 200 m away, yikes! This persistent weak layer is expected to be a concern for some time; at all elevations and aspects. Treeline and below treeline is catching a lot of people by surprise.

Problems

Persistent Slabs

Expect the deeply buried weak layers to continue to produce very large and destructive avalanches. Slopes are primed for human triggering and it remains a concern on all aspects and elevations.

Use conservative route selection and resist venturing out into complex terrain, even if you observe no obvious signs of unstable snow.>Remote triggering is a big concern, be aware of the potential for wide propagations and large, destructive avalanches at all elevations.>Avoid areas with overhead hazard.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

3 - 6

Wind Slabs

Wind has transported snow and built fresh, touchy wind slabs. Be aware of weak cornices looming over slopes. If they fail, it will likely a trigger large slab avalanche on the slope below.

Avoid freshly wind loaded features.>Extra caution needed around cornices with current conditions.>Use conservative route selection, stick to moderate angled terrain with low consequence.>

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

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 4

Valid until: Feb 23rd, 2014 2:00PM