Avalanche Forecast

Issued: Jan 18th, 2016 7:59AM

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

pgoddard, Avalanche Canada

South Columbia.

A touchy persistent slab problem demands respect. Use extra caution in your terrain selection.

Summary

Confidence

Moderate - Timing of incoming weather systems is uncertain

Weather Forecast

Fairly benign weather is expected for the next couple of days ahead of the next storm due late Thursday. Overnight Monday: 5-10 cm snow; Tuesday/ Wednesday: flurries; Thursday: 10-20 cm. The freezing level drops from 1100 m to valley floor late on Tuesday. Moderate southerly winds become light by late Tuesday. For more details check out http://www.avalanche.ca/weather.

Avalanche Summary

Avalanche activity has been widespread over the last few days as recent snow has reached a critical load above a volatile weak layer. Human and naturally-triggered avalanches in the size 1-2.5 range have been most prevalent below treeline, but have also occurred at treeline and alpine elevations. Wind slabs have also been reported in wind-exposed terrain. A ski tourer was buried last week, and professionals continue to operate with great caution. Continued human triggering of persistent slab avalanches is likely.

Snowpack Summary

A 40-80 cm persistent slab overlies a variety of surfaces including large surface hoar, sun crusts, and facets. This slab is ripe for human triggers and is especially touchy below treeline. Recently formed wind slabs also exist on lee features at alpine and treeline elevations. The mid and lower snowpack are generally well settled and strong.

Problems

Persistent Slabs

The slab sitting over a volatile weak layer is primed for human triggering. It has been most reactive at and below treeline.

Extra caution required below treeline.>Avoid steep open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>Use conservative route selection.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 4

Wind Slabs

Recently formed wind slabs may be lurking behind ridges and ribs.

Avoid lee and cross-loaded terrain near ridge crests.>Use ridges or ribs to avoid pockets of wind loaded snow.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Jan 19th, 2016 2:00PM