Avalanche Forecast

Issued: Jan 7th, 2019 8:00AM

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

Chris Gooliaff, Parks Canada

Glacier.

Surface slabs are developing with the increased winds in the alpine. Use terrain to your advantage and avoid convex rolls or large, planar slopes.

Summary

Weather Forecast

Convective cells passing through the region will bring isolated flurries between sunny breaks. Alpine highs of -12*C and moderate SW winds will keep things cool. Similar conditions Tuesday, with light/moderate SW winds, isolated flurries, and alpine highs of -7*C. A system rolls through Wed/Thurs, bringing 10-15cm and rising freezing levels (1600m)

Snowpack Summary

Recent snowfall is now being redistributed in the alpine by moderate SW winds. Cornices grew considerably during last week's storm and are looming along ridgecrests. Persistent weak layers from December are buried deep in the snowpack and will need a large trigger to wake up. An early season crust is decomposing at or near the ground.

Avalanche Summary

Natural activity has decreased, with several sz 2 slabs from the Macdonald north-side gullies observed yesterday. Tests in the Hermit basin found broken results down 100cm at the storm interface We could not get anything to move with ski-cutting steep features below tree-line. Similar results were found in the Asulkan. Limited alpine obs

Confidence

Due to the number of field observations

Problems

Wind Slabs

Moderate SW winds are moving around last week's storm snow and forming soft slabs in lee and cross-loaded features. We have limited alpine observations, so they may be more widespread than just lee features.

If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Use caution in lee and cross-loaded areas. Recent wind loading has created new wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2.5

Cornices

Strong winds, warm temps, and over a 100cm of snow in the last week has allowed cornices along ridge-tops to grow. Minimize time underneath these hulking beasts, and give them a wide berth if you are traveling along a ridgecrest.

Stay well back from cornices.Pay attention to overhead hazards like cornices which could easily trigger persistent slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3.5

Valid until: Jan 8th, 2019 8:00AM