Avalanche Forecast

Issued: Mar 30th, 2014 9:10AM

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

mbender, Avalanche Canada

Kootenay Boundary.

Summary

Confidence

Good

Weather Forecast

Monday: Mix of sun and cloud. Light west winds. Freezing level 1500m.Tuesday: Mainly sunny with some cloudy periods. Light westerly winds. Freezing level 1600m.Wednesday: Mainly sunny with some cloudy periods. Light north winds. Freezing level 1500m.

Avalanche Summary

Recent avalanche activity has been reported as loose dry and moist avalanches running to size 1.5 in steep terrain. In addition a few natural and explosives triggered avalanches to size to 2 on SE and NW aspects at and above tree-line.

Snowpack Summary

Up to 35cm of recent new snow sits on top of a melt-freeze crust formed on March 25 on all aspects except steep north at tree-line and above. There is now 60 - 90cm of new snow on top of the March 10th crust. This crust is widespread to 2000m across the region, perhaps even higher on solar aspects. There are reports of the crust being as thick as 15cm in the south of the region, however there seems to be variability in how thick and supportive it is. As you head north in the region where the mountains are higher (temperatures were colder when the crust was forming) this crust is less likely to exist. If you are heading to the north of the region make sure you check out the South Columbia bulletin also.A facet/crust persistent weakness buried at the beginning of February, now down 70 - 200cm, has been highly variable in terms of reactivity but still shows 'sudden' results in some snowpack tests. In areas where the strong and supportive crust exists, triggering this layer has become unlikely. That said, any avalanches triggered on this deep persistent layer would be large and destructive.

Problems

Wind Slabs

Recent moderate west winds have created wind slabs in the lee of terrain features.

Be cautious as you transition into wind affected terrain.>Use ridges or ribs to avoid pockets of wind loaded snow.>Stay well to the windward side of corniced ridges.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Deep Persistent Slabs

Triggers for large avalanches on deeply buried layers include cornice falls, solar warming, or hitting the wrong place in a thin snowpack area.

Avoid convexities or areas with a thin or variable snowpack.>Be aware of the potential for large, deep avalanches due to the presence of buried weak layers.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

2 - 5

Valid until: Mar 31st, 2014 2:00PM