Avalanche Forecast

Issued: Jan 22nd, 2016 8:07AM

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

Avalanche Canada pgoddard, Avalanche Canada

A Special Public Avalanche Warning is in effect for this region.

Summary

Confidence

Moderate - Timing or intensity of solar radiation is uncertain

Weather Forecast

A cooling and drying trend is expected to start on Saturday. Cloudy skies, light winds, cool temperatures and a few flurries are expected on Saturday, with sunny skies possible on Sunday/ Monday.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 this week. 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 seem to have been somewhat limited in distribution across the region. On Friday, a large natural avalanche cycle to size 3.5 was reported by one operator near Valemount. In other parts of the region, the persistent slab may not get such a good clean-out and the problem may linger for human-triggering beyond the end of the storm.

Snowpack Summary

Heavy new snow and strong winds have created storm slabs in many places 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 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

An icon showing Persistent Slabs
Numerous persistent slabs have been triggered this week. Even as the weather improves, this problem could remain touchy.
Use conservative route selection and be aware of the potential for remote triggering. >Extra caution required in open terrain features at and below treeline.>Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 6

Storm Slabs

An icon showing Storm Slabs
The recent storm has created storm slabs in many areas, and wind slabs on slopes lee to the south. These could be easy to trigger with the weight of a person or sled.
Travel on ridgetops to avoid wind slabs on slopes below.>Avoid lee and cross-loaded terrain near ridge crests.>Choose conservative lines and watch for clues of instability.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 5

Valid until: Jan 23rd, 2016 2:00PM