Avalanche Forecast

Issued: Dec 9th, 2018 5:08PM

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

Avalanche Canada dsaly, Avalanche Canada

Its snowing! Storm slabs are forming at higher elevations and not expected to bond well to the old snow surface.

Summary

Confidence

Low - Intensity of incoming weather systems is uncertain

Weather Forecast

SUNDAY NIGHT: Flurries, up to 20 cm accumulating overnight, moderate south west wind, freezing level 1000 mMONDAY: Flurries, 5 -15 cm snow expected, moderate south-southwest wind, freezing level 1200mTUESDAY: Snow, accumulation up to 45cm, moderate southwest wind with strong gusts, freezing level 1100mWEDNESDAY: Continued snow, accumulating 20-30 cm, moderate southwest wind with strong gusts, freezing level below 1000m

Avalanche Summary

Prior to the new snow, reverse-loading winds have created small (size 1) wind slabs in lee features which are reactive to skier traffic around the Whistler area. On steep, sun exposed features in the alpine, solar warming has produced small (size 1) loose snow avalanches over the past few days. Avalanche activity will depend on new snow bonding with the old surface layer.

Snowpack Summary

Snowfall beginning Sunday has added up to 30cm around the region. The new snow has buried a weak surface layer sitting over 20-30 cm of low density faceted snow and the new snow is initially not expected to bond well with the older snow.Prior to this storm, alpine snowpack depths varied around 150-200 cm, with an early November crust at bottom of the snowpack (down 100-120cm). This crust appears to be breaking down at higher elevations and has been unreactive to snowpack tests. Snowpack depths disappear quickly with decreasing elevations (starting around 1800m).

Problems

Storm Slabs

An icon showing Storm Slabs
Snow began accumulating on Sunday and around 30 cm new snow has been deposited around the region accompanied with moderate winds. Storm slabs have begun to develop and, initially the new snow is not expected to bond well with old snow.
Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.Use caution in ridge crests and lee areas. Recent snowfall mixed with wind has created storm slabs.Minimize overhead exposure during periods of heavy loading from new snow, wind.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Valid until: Dec 10th, 2018 2:00PM