Avalanche Forecast

Issued: Jan 20th, 2018 4:38PM

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

Avalanche Canada jmcbride, Avalanche Canada

With a strong winter storm system set to bring heavy snowfall and high winds, Sunday looks like a good day to enjoy the resort.  Or stick to simple terrain free of overhead hazard if you choose to venture into the backcountry.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain

Weather Forecast

TONIGHT: Snow. Accumulation 30-40 cm. Ridge wind strong to extreme, south. Temperature -5. Freezing level 1000 m.SUNDAY: Snow. Accumulation 25-35 cm. Ridge wind strong to extreme, south. Temperature -4. Freezing level 1000 m.MONDAY: Flurries. Accumulation 5-10 cm. Ridge wind light to moderate, southwest. Temperature -4. Freezing level 900 m.TUESDAY: Snow. Accumulation 15-20 cm. Ridge wind strong, south. Temperature -4. Freezing level 900 m.

Avalanche Summary

Both natural and human triggered avalanches are likely with intense loading from forecasted snowfall and wind amounts.Explosive control work on Friday produced only a few size 1 and isolated size 2 avalanches failing in the recent storm snow or running on the recently buried January 15th crust. On Thursday there were reports of natural avalanches up to size 2.5, while ski cuts and explosive control work produced numerous size 1-1.5, and up to size 2, storm slab avalanches 20-50 cm deep on predominantly northerly aspect, running far and wide within the recent storm snow.Earlier in the week ski cutting and explosive control work produced numerous easily triggered size 1-1.5 storm slab results running on the January 15th crust.

Snowpack Summary

Above 1400 m elevation, 40-70 cm of storm snow overlies the crust that was buried mid-January and is present at all elevations. This crust is thin on northerly aspects and up to 3 cm thick on solar aspects. Below this crust 30-40 cm well settled snow overlies a second crust that was buried early-January and now lies about 100 cm below the surface at elevations up to 2000m. Beneath the early-January crust, the lower snowpack is generally strong and well settled. Recent snowpack tests have produced easy to moderate, resistant results within the recent storm snow as well as hard, resistant results above the recently buried mid-January crust.

Problems

Storm Slabs

An icon showing Storm Slabs
Storm snow and strong winds have formed reactive storm slabs. These slabs overlie recently buried wind slab and a recent melt-freeze crust, and will continue to build with more snow and wind in the forecast.
Avoid all avalanche terrain during periods of heavy loading from new snow and wind.The new snow will take time to settle and stabilize.Whumpfing, shooting cracks and recent avalanches are all strong indicators of an unstable snowpack.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1.5 - 3

Valid until: Jan 21st, 2018 2:00PM