Avalanche Forecast

Issued: Nov 23rd, 2018 4:44PM

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

Avalanche Canada kdevine, Avalanche Canada

Forecasts contain a high degree of uncertainty due to a lack of field observations. Conservative terrain selection is recommended.

Summary

Confidence

Low - Due to the number of field observations

Weather Forecast

FRIDAY NIGHT- Cloudy with clear periods / light northerly winds / freezing level at valley bottom / no new snow expectedSATURDAY - Mainly cloudy / isolated flurries / light southwest to west winds / freezing level 1000m / alpine temperatures near -7SUNDAY - Cloudy with sunny periods / isolated flurries / light to moderate southwest winds / freezing level 1100m / alpine temperatures near -10MONDAY - Snow, total snowfall amounts vary greatly throughout the region with 5-10cm forecast in the Selkirks and up to 20cm in the Monashees / light to moderate south winds / alpine temperatures near -5.

Avalanche Summary

There have been recent reports of natural loose snow avalanches to size 1.5, and several slab avalanches to size 2 triggered with explosives. There are currently very limited field observations in this region and it is critical to supplement this information with your own observations. Please submit your observations to the Mountain Information Network (MIN).

Snowpack Summary

25-50cm of new snow has fallen since November 21. Light to moderate southerly winds have likely created a storm slab which sits on top of a weak layer that consists of surface hoar (weak feathery crystals), sun crust on steep south facing slopes, and old wind slabs in the alpine. The surface hoar is most prevalent at treeline and below, but it may exist in sheltered alpine areas. It is possible that some wind loaded areas could have over 100cm of snow on top of this weak layer.Deeper in the snowpack there are two crusts that formed in late October and mid November. Information on these layers is limited due to a lack of field observations, but there have been no recent reports of avalanches or significant test results on these layers.The total snowpack depth varies greatly with elevation. Recent reports show depths of 120-200cm in the alpine, 80-145cm at treeline and 10-90cm below treeline.

Problems

Storm Slabs

An icon showing Storm Slabs
New snow and wind have formed storm slabs in lee terrain features.
Avoid freshly wind loaded features.Forecasters are operating with a lot of uncertainty at this time.Make observations and assess conditions continually as you travel.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Nov 24th, 2018 2:00PM