Avalanche Forecast

Issued: Dec 10th, 2013 8:09AM

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

ali haeri, Parks Canada

Glacier.

Expect fast moving sluffs with the potential to know you over today and be mindful of people below you.

Summary

Weather Forecast

Nil to very light snow is forecast until Wednesday night when more significant precipitation is expected to arrive to the interior with a gradual warming in temperature.

Snowpack Summary

25cm of low density storm snow sits over the December 8 surface hoar layer at lower elevations and over variable wind slabs up high. The November 28 surface hoar layer is down around 35-40cm over a facetted mid and lower snowpack. The November 12 surface hoar layer is down 60-110cm.

Avalanche Summary

1 natural avalanche size 1.5 yesterday east of the Rogers Pass summit on Mt Macdonald.

Confidence

Problems

Loose Dry

25cm of new snow sits over a newly buried surface hoar layer down low and wind slabs up high. Riders should expect sluffing in steep terrain that could reach down into deeper unconsolidated layers and gain mass.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.Be aware of party members below you that may be exposed to your sluffs.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Wind Slabs

Variable hard and soft wind slabs from last week are now buried down 25cm.

Be cautious as you transition into wind affected terrain.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

The surface hoar layer from mid November is buried down 60-110cm. Triggering this layer is most likely in and around shallow snowpack areas with large consequences.

Be aware of thin areas that may propogate to deeper instabilites.Dig down to find and test weak layers before committing to a line.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

3 - 4

Valid until: Dec 11th, 2013 8:00AM