The Revelstoke-based Canadian Avalanche Centre on Feb. 20 issued a special public avalanche warning for recreational backcountry users. They’re warning of the “worst weak layers” in years buried deep in the snowpack. A long dry spell was followed by over a week of heavy snowfalls, meaning backcountry enthusiasts are keyed up for powder this weekend.
The avalanche forecaster issues special public avalanche warnings based on a number of factors, including relative avalanche danger and the likelihood of high backcountry traffic.
In their own words, here’s the Feb. 20 media release from the CAC:
Special Public Avalanche Warning for Most of BC’s Mountainous Regions
Canadian Avalanche Centre warns of significant potential for large, destructive avalanches in forecast regions
Feb 20, 2013, Revelstoke, BC: The Canadian Avalanche Centre (CAC) is issuing a special public avalanche warning for recreational backcountry users in all of the CAC’s forecast regions, except the North Shore Mountains and the Yukon. This warning is in effect immediately and extends to the end of the day on Wednesday, February 26.
The problem is a result of the extended dry period of late January and early February, explains Karl Klassen, Manager of the CAC’s Public Avalanche Warning Service. “That long drought left the surface of the snowpack in very bad shape,” says Klassen. “Now the new snow is sitting on one of the worst weak layers we’ve seen in a few years. That weakness is currently anywhere between one and two metres deep so when it’s triggered, the resulting avalanches are very large.”
The problem layer is widespread and with a weather forecast calling for clearing skies, the CAC is urging recreational backcountry users to be very conservative in their terrain choices. “There’s a lot of pent-up demand for powder after that dry spell but this weak layer is going to be a problem for the foreseeable future,” says Klassen. “Staying safe will require patience and discipline as long as this layer is in play.” The weak layer will likely persist after this warning expires and recreationists are urged to stay cautious in avalanche terrain.
Everyone in a backcountry party needs to carry an avalanche transceiver, probe and shovel and be well-practiced with their rescue skills. The CAC strongly recommends that backcountry users take an Avalanche Skills Training course, and check the avalanche bulletin regularly to keep informed of conditions in their area. More detailed information is also available on the CAC blogs and forecasts at ww.avalanche.ca/cac