Avalanche Forecast

Issued: Feb 2nd, 2013 9:28AM

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

jlammers, Avalanche Canada

Kootenay Boundary.

Summary

Confidence

Fair - Due to variable snowpack conditions

Weather Forecast

Sunday: Very light snowfall occurring late in the day / Moderate to strong northwest winds / Alpine temperature of -1.0Monday: Very light snowfall / Moderate to strong northwest winds / Alpine temperature of -5.0Tuesday: Light snowfall / Light southwest winds / Alpine temperature of -7.0

Avalanche Summary

I would suspect some solar-induced loose wet avalanche activity in response to warming and strong solar input on Saturday. Human-triggered slabs (size 1 to 1.5) have also been failing on the Jan 23 interface. In many cases, these events have been on wind-loaded aspects.

Snowpack Summary

Recent NW winds have redistributed 15-40 cm of recent snow into soft or hard slabs on lee slopes in the alpine and at treeline. A weak interface of surface hoar, facets or sun crust buried on Jan 23 continues to be a concern among professionals in the region. Deeper, about 50-60cm down, a weak interface buried in early January has still shown moderate to hard, sudden results in snowpack tests. The snowpack below this is generally well bonded.

Problems

Wind Slabs

Be alert for wind slabs behind terrain breaks such as ridges and ribs.

Avoid travelling in areas that have been reverse loaded by winds.>Be aware of the potential for wide propagations due to the presence of hard windslabs.>Be cautious as you transition into wind affected terrain.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Persistent Slabs

A mixed bag of weak interfaces is buried about 40 cm down. The nature of these weaknesses may vary considerably from slope to slope.

Make observations and assess conditions continually as you travel.>Choose well supported terrain without convexities.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Feb 3rd, 2013 2:00PM