Avalanche Forecast

Issued: Jan 31st, 2016 8:11AM

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

percy woods, Parks Canada

Glacier.

Moderate to strong S winds have loaded lee features the last two nights. The storm snow should be primed for human triggering.

Summary

Weather Forecast

Cooling trend with light winds, alpine temps to -8C and cloudy with sunny periods. Tomorrow expect light flurries, light winds and continued cooling air temps.

Snowpack Summary

Last week's storm produced 50cm of storm snow which is now settling into a surface slab. The bond of this layer will be improving but it should not be discounted in travel plans. Wind slabs should be expected on lee features after mod-strong S-SW winds last two nights. Jan 4th interface down 60-100cm may be touchy in areas where it has not failed.

Avalanche Summary

Half a dozen size slides in the size 1.5-2.5 size yesterday in the highway corridor likely triggered by moderate to strong winds. Overall natural activity has subsided since the avalanche cycle Thursday.

Confidence

Due to the number of field observations

Problems

Storm Slabs

Expect the storm slab to be touchy after another night of moderate S-SW winds. On lee features and exposed areas the cohesive slab could be upwards of 60cm thick. If triggered slides may step down to deeper weak layers.

The new snow will require several days to settle and stabilize.If triggered the storm slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Persistent Slabs

The January 4th interface was recently rapidly overloaded. This layer is tricky to assess as it is not evenly distributed on the landscape. It is also only sporadically reactive. It can be found in many locations 60-100cm down in the snowpack.

Carefully evaluate terrain features by digging and testing on adjacent, safe slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Feb 1st, 2016 8:00AM