Avalanche Forecast

Issued: Feb 1st, 2019 5:30PM

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

kdevine, Avalanche Canada

South Columbia.

The South Columbia received highly variable snowfall amounts in the storm with the highest amounts near the Revelstoke area. Hazard is likely HIGH in the mountains near Revelstoke. South of Trout Lake is likely well represented by this bulletin.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain

Weather Forecast

FRIDAY NIGHT - Flurries, 10-15 cm / southwest winds, 30-50 km/h / alpine low temperature near -7SATURDAY - Cloudy with scattered flurries, 3-5 cm / southwest winds 20-30 km/h / alpine high temperature near -7SUNDAY - Mainly cloudy with isolated flurries, 5 cm / southeast winds 10-15 km/h / alpine high temperature near -12MONDAY - Mainly cloudy / northeast winds, 10-15 km/h / alpine high temperature near -14

Avalanche Summary

Field observations were limited on Friday, but a widespread natural avalanche cycle, as well as numerous human triggered avalanches to size 1.5 were reported.On Tuesday, in the neighboring Glacier National Park region, a size 3 avalanche was skier triggered on a steep southeast facing slope in the alpine. More details and photos here.

Snowpack Summary

20-50 cm of new snow has fallen in the region since Thursday.Â The highest amounts fell near Revelstoke, and the amounts taper significantly south of Trout Lake. This new snow sits wind slab, surface hoar (feathery crystals), facets (sugary snow) and a crust on sun-exposed slopes. A persistent weak layer that was buried in mid January is now buried 35-85cm. This layer consists primarily of surface hoar, however there is also a crust associated with it on sun-exposed slopes. This layer has been most reactive at treeline and below.

Problems

Storm Slabs

20-50 cm of new snow has fallen in the region since Thursday. It will take some time for this snow to bond to the underlying snow.

If triggered, slabs or sluffs may step down to deeper layers and result in even larger avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Persistent Slabs

45-100 cm of snow sits above a weak layer of surface hoar (feathery crystals) and crust. This layer will likely be reactive due to recent snowfall.

Use extra caution around steep open terrain features, such as cutblocks, gullies and cutbanks.Avoid convex rolls at and below treeline where buried surface hoar may be preserved.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Valid until: Feb 2nd, 2019 2:00PM