Avalanche Forecast

Issued: Jan 1st, 2017 8:04AM

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

Parks Canada percy woods, Parks Canada

Happy New Year!  Watch for freshly formed windslab and reverse loading along wind exposed terrain.

Summary

Weather Forecast

Mainly cloudy with N-E moderate to strong winds and cold alpine temps of -17C today. Clear and cold for Monday, Tuesday with more NE flow of cold air.

Snowpack Summary

60cm+ of storm snow was initially redistributed by mod-storng S wind Friday. Overnight 8hrs of strong N-NE wind has worked to reverse load alpine and wind exposed treeline features. 80cm of snow now overlies the Dec 18th facet interface, which was reactive to artillery control on Friday. Expect fresh reactive windslab in the alpine all aspects.

Avalanche Summary

There was a widespread natural avalanche cycle on Friday up to size 3 on all aspects and elevations. Yesterday no new avalanches were reported or observed.

Confidence

Due to the number of field observations

Problems

Wind Slabs

An icon showing Wind Slabs
Moderate to strong winds, first from the S Friday and now from the N-NE, have redistributed 60cm+ of recent storm snow. Dec18 Facet interface down 80cm  is a major feature of the snowpack and should not be discounted in your evaluation.
Watch for whumpfing, hollow sounds, and shooting cracks.If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Storm Slabs

An icon showing Storm Slabs
Since Thursday we have received 60cm+ snow at 1900m elevation which is settling into a slab. Expect the forming slab to be most reactive at and above TL. The storm slab did step down to the Dec 18th interface with artillery and explosive control.
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

Likely

Expected Size

1 - 3

Valid until: Jan 2nd, 2017 8:00AM