Avalanche Forecast

Issued: Dec 12th, 2019 4:00PM

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

Avalanche Canada kdevine, Avalanche Canada

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Although the storm has eased off, storm slabs at upper elevations are still likely to be encountered and could be reactive to human triggering, especially in wind loaded areas.

Summary

Confidence

Low - Uncertainty is due to the limited number of field observations.

Weather Forecast

THURSDAY NIGHT - Flurries, 5 cm / west winds, 20-30 km/h / alpine low temperature near -1 / freezing level 1000 m

FRIDAY - Mainly cloudy with isolated flurries. 2-4 cm / light southwest winds / alpine high temperature near -1 / freezing level 900 m

SATURDAY - Cloudy with sunny periods / light west winds / alpine high temperature near -4 / freezing level 600 m

SUNDAY - A mix of sun and cloud / light northwest winds / alpine high temperature near -4

Avalanche Summary

There have been no recent reports of avalanches, but there is very little information available at this time. Based on recent weather events, it is likely that a natural avalanche cycle occurred at upper elevations on Thursday, and may continue into Friday.

If you get out into the mountains, let us know what you see by posting to the Mountain Information Network!

Snowpack Summary

A heavy storm hit the south coast on Wednesday and delivered up to 80 mm of precipitation in some areas by Thursday night. The precipitation generally fell as snow above 800 m, and rain below. Observations are limited, but most areas seem to have received between 30-50 cm of snow at treeline and in the alpine. Above about 1400 m this new snow reportedly sits on weak surface hoar crystals in many locations, and sugary faceted snow in some areas. Strong southwest winds have likely redistributed the new snow and formed reactive storm slabs. The new snow sits on a very thin snowpack of about 30 cm at 1500 m in the North Shore mountains.

Problems

Storm Slabs

An icon showing Storm Slabs

Recent heavy snowfall and strong winds have formed fresh storm slabs at upper elevations. These slabs sit on a weak layer of surface hoar and may be reactive to human triggers, especially in wind loaded areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Dec 13th, 2019 5:00PM