Forecast snowfall is uncertain, but fresh storm slabs are set to form over a new weak layer on Thursday. Natural storm slab releases could provide ample triggers for deeper persistent weak layers.
Avalanche Problem 1: Storm Slabs




- Strong southwest winds will likely form thicker, more sensitive slabs on northeast aspects.
- If triggered, storm slabs may step down to deeper layers and result in large avalanches.
Avalanche Problem 2: Persistent Slabs




Large avalanches may be triggered on a number of buried weak layers, even in fairly dense trees and shallow slope angles. Stress on these weak layers will increase as new snow and wind load the snowpack on Thursday.
- Minimize exposure during periods of heavy loading from new snow and wind.
- Avoid lingering or regrouping in runout zones.
- Be wary of slopes that did not previously avalanche - even on low angle terrain.
Avalanche Summary
Very significant avalanche activity occurred in the region last week. Large avalanches ran on multiple persistent weak layers, even in fairly dense trees and low angle slopes. Activity has gradually tapered off, but the potential for human triggering remains. On Tuesday, explosive control in the Lizard range produced a few large persistent slab avalanches on deep weak layers (size 2-2.5). Recent natural activity was also reported in the Sparwood area.
Snowpack Summary
Light new snow amounts have begun to give a thin cover to a new layer of feathery surface hoar on sheltered aspects (especially prominent from 1400-1900 m) as well as sun crust on solar aspects. Recent warm temperatures created this crust and also worked to settle the upper snowpack. Shifting winds during the warm period transported snow from last week, leaving old wind slabs in open terrain as well as cornices along ridges.
A number of buried weak layers have been very concerning over the past week, and appear to be gaining strength very slowly. The early January surface hoar layer is around 60 cm below the surface and the unstable weak layer from mid-December (predominantly surface hoar and/or a sun crust) is around 100 cm below the surface at treeline and below treeline elevations. A rain crust with sugary facets that developed late-November is near the bottom of the snowpack. All of these layers have been reactive over the past week.
Weather Forecast
Wednesday night: Flurries bringing 3-5 cm of new snow. Strong southwest winds.
Thursday: Cloudy with continuing flurries bringing 5-20 cm of new snow. Strong southwest winds. Freezing level to 1700 metres with alpine high temperatures around 0 to -1.
Friday: Mainly cloudy. Moderate southwest winds. Freezing level falling to around 1100 metres with alpine high temperatures of -5.
Saturday: Mainly cloudy. Moderate southwest winds. Freezing level near the surface with alpine high temperatures around -6.
Avalanche Forecasts in your Inbox
Avalanche Canada has switched to an RSS feed for its daily forecasts. This is a much more flexible method that allows automatic delivery to your email inbox, or to an RSS reader of your choice.
What are RSS feeds?
RSS (Really Simple Syndication) is a popular standardized file format allowing up-to-date delivery of web-based content. RSS feeds enable you to receive content updates from websites, delivered to your email through an RSS aggregator (such as blogtrottr.com) or viewed through applications called RSS readers (such as feedly.com).
Set up an RSS feed for your email:
Select a RSS aggregator
- Lizard Range and Flathead URL:
http://www.avalanche.ca/api/forecasts/lizard-range.rss - Copy the url and paste it into the appropriate field of your RSS aggregator.
- Fill in your email address.
- Voila! Watch the Avalanche Canada forecast roll into your inbox.
Forecast Disclaimer
Avalanche Canada's Public Avalanche Bulletin, and other information and services provided by Avalanche Canada, are intended for personal and recreational purposes only.
**THIS INFORMATION IS PROVIDED "AS IS" AND IN NO EVENT SHALL THE PROVIDERS BE LIABLE FOR ANY DAMAGES, INCLUDING, WITHOUT LIMITATION, DAMAGES RESULTING FROM DISCOMFORT, INJURY, OR DEATH, CLAIMS BY THIRD PARTIES OR FOR OTHER SIMILAR COSTS, OR ANY SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, ARISING OUT OF THE USE OF THE INFORMATION.**
The user acknowledges that it is impossible to accurately predict natural events such as avalanches in every instance, and uses the data in this bulletin with this always foremost in mind. The accuracy or reliability of the data is not guaranteed or warranted in any way and the Providers disclaim liability of any kind whatsoever, including, without limitation, liability for quality, performance, merchantability and fitness for a particular purpose arising out of the use, or inability to use the data.
New snow will form fresh storm slabs over a new weak layer on Thursday. The new snow is not expected to bond well and winds may make slabs extra touchy. A small storm slab release could provide enough stress to trigger a deeper persistent weak layer.