Avalanche Forecast

Issued: Jan 12th, 2013 4:00PM

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

chris gooliaff, Parks Canada

Banff Yoho Kootenay.

Touchy conditions exist where the wind has created soft slabs at tree-line and alpine elevations. Even though the danger ratings are Moderate, if you observe whumphing or cracking, you might want to choose a more conservative line.

Summary

Weather Forecast

The ridge of high pressure will continue for tomorrow, giving the region clear skies, light northerly winds, and cool (-15 to -20) temp's. By Monday, however, expect temp's to increase and winds to pick up to moderate/strong from the NW, bumping the avalanche hazard up again. There is still a lot of snow to be whipped around by the wind.

Snowpack Summary

Up to 50cm of recent storm snow sits atop a variety of old surfaces: surface hoar and facets at and below tree-line, and wind or sun crusts in the alpine. Storm slabs were also buried during the storm. Where the wind has redistributed the new snow, whumphing and cracking was observed today, suggesting human-triggering is still possible.

Avalanche Summary

Natural activity has decreased and no new avalanches were observed. This being said, the field team observed whumphing and cracking at tree-line elevations where there had been wind during and after the storm. There were slabs buried during the storm, so even though the surface looks fluffy, there may be hidden slabs awaiting on windward slopes.

Confidence

Due to the number and quality of field observations

Problems

Storm Slabs

Today, a field team observed whumphing and cracking at tree-line elevations where wind had created soft slabs. These slabs felt touchy on these specific, wind-affected areas. Human-triggering is still possible, given the right load on the sweet spot.

Be cautious as you transition into wind affected terrain.Dig down to find and test weak layers before committing to a line.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Jan 13th, 2013 4:00PM