A cycle of storms set in over B.C. this weekend and avalanche forecasters are warning backcountry users
On Dec. 21, Avalanche Canada forecasted High avalanche danger ratings for the Roger’s pass and North Columbia avalanche regions.
The dangerous avalanche conditions are due to increased loading of new snow brought on by weekend storms that hammered B.C. with anywhere from five to 25 centimetres daily since Thursday.
The new snow, which buried a weak layer in the snowpack that formed in early December,, rising temperatures and strong winds are all factors that elevated the avalanche danger ratings.
Danger ratings are expected to peak Monday with additional snowfall and strong winds forecasted for overnight tonight.
The persistent weak layer is now expected to be buried by a 40 to 60 centimetre slab of storm snow in the North Columbia region and over one metre in Rogers Pass. Both regions have found the weak layer of snow at all elevation levels and slope aspects. They are very likely to be triggered by human or natural causes and failure of the weak layer can set off very large avalanches.
A widespread natural avalanche cycle has already been observed in Roger’s Pass on Saturday night and Sunday morning. Natural and artillery controlled avalanches were set off up to size three and a half.
In North Columbia, natural avalanches up to size three were observed Friday and Saturday and the new snow is expected to bring more natural avalanche activity that may persist.
In a blog released on Dec. 17, Avalanche Canada’s forecasting program supervisor James Floyer recommended staying within the safety of a ski area boundary, or if you’re a sledder, sticking to the groomed trail network.
“If you do venture further, stick to simple terrain that’s less than 30 degrees and is not threatened by avalanche paths from above,” he wrote.
Navigating avalanche terrain during high and extreme avalanche danger is an advanced skill.
Make sure to get the gear, training and know-how by visiting www.avalanche.ca to find Avalanche Safety Training (AST) providers in your area, avalanche forecasts, online learning tutorials and more before venturing into any avalanche terrain.