Avalanche Forecast

Issued: Jan 21st, 2016 9:10AM

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

pgoddard, Avalanche Canada

Cariboos.

Variable conditions across the region. Wind and snow over a touchy weak layer are expected to increase avalanche danger on Friday.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain

Weather Forecast

Friday brings another 10-20 cm snow, strong S to SW winds and freezing levels around 1100 m. Winds are mainly light, temperatures drop and there may be a few flurries through the weekend.For more details check out http://www.avalanche.ca/weather.

Avalanche Summary

Numerous large (size 2-3) persistent slabs failed naturally or with artificial triggers on Tuesday and Wednesday. Many of these were remotely triggered, highlighting the extreme sensitivity of the buried weak layer. These events appear to be on all elevations and aspects, but the distribution of this type of avalanche activity across the entire region is a little uncertain.

Snowpack Summary

New snow and strong winds are likely to create storm slabs and wind slabs on features lee to the south. This will also add load and stress to the already volatile persistent slab. There are a couple of highly reactive layers of surface hoar buried in the upper snowpack, which have been responsible for lots of recent avalanches. The mid and lower snowpack are generally strong, with any weak layers considered dormant for now. Snowpack depths are variable and shallow snowpack areas may have weak facetted crystals near the ground.

Problems

Persistent Slabs

Numerous large persistent slabs have been triggered over the last few days on many aspects and elevations. New storm loading will only accentuate this problem.

Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>Extra caution required in open terrain features at and below treeline.>Use conservative route selection and be aware of the potential for remote triggering. >Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 5

Storm Slabs

New snow and strong southerly winds are expected to create a storm slab problem. Storm slabs/ wind slabs may pick up a surprising amount of mass due to the existence of a persistent weak layer.

Avoid lee and cross-loaded terrain near ridge crests.>Travel on ridgetops to avoid wind slabs on slopes below.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 5

Valid until: Jan 22nd, 2016 2:00PM