Metro Vancouver residents will want to keep the umbrellas and galoshes handy Thursday and Friday, as yet another atmospheric river bears down on B.C.’s South Coast.
Environment Canada issued a rainfall warning for the region, along with special weather statements for Greater Victoria, the Fraser Valley, the Sunshine Coast, eastern Vancouver Island and the Southern Gulf Islands. A snowfall warning is also in effect for the Sea-to-Sky region from Squamish to Whistler.
“Big storm hitting the B.C. coast. It’s going to whip through the entire province over the next day and a half or so,” Global BC chief meteorologist Mark Madryga said Thursday.
“We’ll likely end up in the Lower Mainland with between 40 and 80 mm of rain before we’re done sometime late tomorrow.”
Rain is forecast to develop across the coast through the day Thursday, before intensifying into the evening and through Friday — finally tapering off late in the day.
The freezing level is also forecast to fall as low as 300 metres Thursday, meaning a chance of light snow in areas like Burnaby Mountain and Coquitlam’s Westwood Plateau, before milder subtropical air flows in with the atmospheric river on Friday, Madryga said.
The timing of snow in the Sea-to-Sky corridor is forecast to largely mirror rainfall in the Lower Mainland, with snowfall intensifying overnight and with accumulations of between 15 and 20 cm by Friday morning.
Snowfall warnings are also in effect for the Highway 3 and the Coquihalla and Okanagan Connector highways.
Atmospheric rivers are a common meteorological phenomenon that involve long, narrow bands of moisture in the atmosphere that carry water vapour from the tropics to other regions, where they deposit it as heavy rainfall.
They are a regular part of British Columbia’s weather patterns, but have drawn increased attention from meteorologists and emergency officials in the wake of the 2021 November storms which produced catastrophic floods and mudslides and destroyed highways across southwestern B.C.