Avalanche Forecast

Issued: Jan 18th, 2018 4:42PM

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

jmcbride, Avalanche Canada

South Coast.

Snow and wind are expected to continue however, there is some uncertainty as to just how much snowfall some areas will see. If trail breaking is deep and heavy, storm slabs have likely formed - stick to moderate terrain.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain

Weather Forecast

TONIGHT: Snow. Accumulation 15-20 cm. Ridge wind moderate to strong, southwest. Temperature -1. Freezing level 900 m.FRIDAY: Cloudy, snow. Accumulation 20-30 cm. Ridge wind moderate, southwest. Temperature -1. Freezing level 1000 m.SATURDAY: Cloudy, snow. Accumulation 20-25 cm. Ridge wind moderate, southwest. Temperature -1. Freezing level 1000 m.SUNDAY: Cloudy, snow. Accumulation 20-25 cm. Ridge wind moderate, southwest. Temperature -1. Freezing level 900 m.

Avalanche Summary

Last Tuesday a skier was injured in a loose, wet avalanche on the North Shore mountains when the top 10-15 cm of wet snow released on the January 8th crust. On Friday explosive control produced a size 1 avalanche that released a 45 cm thick slab on a weak layer just above the January 7th crust.

Snowpack Summary

At upper treeline and alpine elevations, 5 cm up to 30 cm of new snow has fallen and now covers the January 17th crust. At lower elevations rain has soaked the upper snowpack which consists of 90 cm of wet to moist snow and three deeper crusts (January 10th, January 8th and January 7th). These remain visible but have been unreactive in recent snowpack tests.Â The snowpack depth at 1000 m is about 150 cm and many early season hazards are still present.

Problems

Storm Slabs

New snow combined with southerly winds will form storm slabs particularly on lee slopes at upper treeline and alpine elevations. These slabs overlie a recent melt-freeze crust and may be easily triggered by a skier or rider.

Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.Use careful route-finding and stick to moderate slope angles with low consequencesMinimize overhead exposure during periods of heavy loading from new snow, wind.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Jan 19th, 2018 2:00PM