Avalanche Forecast

Issued: Feb 28th, 2016 8:00AM

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

andrew jones, Parks Canada

Glacier.

Watch for increasing avalanche hazard as new snow load is added to the February 27 surface hoar/ crust weak layer.

Summary

Weather Forecast

A frontal system moves through the region today bringing moderate snowfall. 15cm of accumulation is expected by Monday morning. Strong SW winds with freezing levels climbing to 1700m this afternoon. Freezing levels drop on Monday as precipitation intensity declines. A second frontal system moves in on Tuesday bringing up to 20cm by late Thursday.

Snowpack Summary

8cm of new snow sits on a breakable crust on SE through W aspects and widespread surface hoar. Soft slabs in the upper 50cm can be found near ridge crests, but are more stubborn to move now. The February 10th surface hoar / sun crust is down 50-90cm and is much less reactive than a few days ago.

Avalanche Summary

No new activity was observed in the highway corridor. We received a report of a skier triggered size 1 soft slab avalanche in Balu Pass, failing 10cm down on the February 27 surface hoar layer.

Confidence

Intensity of incoming weather systems is uncertain

Problems

Storm Slabs

A slab on a weak layer down 10cm will become reactive with additional snow load arriving today. Strong SW winds will encourage slab development on loaded lee features. The slab is poorly bonded to a crust on solar aspects and widespread surface hoar.

Use caution in lee areas in the alpine and treeline. Storm snow is forming touchy slabs.Minimize exposure during periods of heavy loading from new snow and wind.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Persistent Slabs

The Feb 10th layer is buried 50-90cm. In some areas there is surface hoar on a crust, creating a dangerous combination. Sensitivity to triggering is variable among terrain features and careful consideration is required. Dig down and test this layer.

Avoid convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Feb 29th, 2016 8:00AM