A special public avalanche warning is in effect until the end of Monday, May 1 for Western Canada. A dramatic increase in temperatures is expected to destabilize the snowpack across western Canada, resulting in dangerous, destructive avalanches, warns Avalanche Canada.
“The sudden transition from cool, wintry conditions in the alpine to warm temperatures will create dangerous avalanche conditions. The effect of the warm temperatures on the existing snowpack structure means that these avalanches will likely be very large and may run to valley bottoms,” Avalanche Canada says.
Dangerous avalanche conditions exist for all mountainous regions in western Canada and the hazard increases with each day of warm air. Regions with persistent or deep persistent slab avalanche problems will be especially problematic, with avalanches potentially involving the full depth of the snowpack, Avalanche Canada said in a note.
Warming can also initiate large and destructive cornice falls. Cornices can be destructive by themselves but also act as a trigger for destructive deep persistent avalanches. All backcountry users, including hikers and scramblers, and anyone recreating in avalanche terrain are advised to leave a wide margin for error during this warming period, stick to simple, low angle terrain, and avoid all overhead avalanche hazards.
