Avalanche Canada has issued a special avalanche warning for mountainous regions in western Canada due to a dramatic, but expected increase in temperatures.

It says that temperature increase is expected to destabilize the snowpack across western Canada and caused destructive and dangerous avalanches.

“The sudden transition from cool, wintry conditions in the alpine to warm temperatures will create dangerous avalanche conditions,” the warning said. “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.”

Dangerous avalanche conditions – at least a four on a scale of one-to-five – exist in all mountainous regions in western Canada with Avalanche Canada noting the hazard increases with each day of warm air.

2/2 This warning is in place immediately until the end of Monday 1st May 2023. Learn more at https://t.co/W2SDWn5aaW

— Avalanche Canada (@avalancheca) April 27, 2023

“Regions with persistent or deep persistent slab avalanche problems will be especially problematic, with avalanches potentially involving the full depth of the snowpack,” the warning added.

“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, are being told to leave a wide margin for error during this warming period. They’re also being urged to stick to simple, low angle terrain, and avoid all overhead avalanche hazards.

This warning will be in place until at least May 1.