A rainfall warning has been issued for Metro Vancouver and the Fraser Valley, with an "extended" period of precipitation in the forecast.
Environment and Climate Change Canada issued the warning Wednesday, saying the rain is expected to start falling overnight.
Between 60 and 120 millimetres are expected, with the highest amounts predicted to fall on the North Shore near the mountains, in Coquitlam and in Maple Ridge, and in the western part of the Fraser Valley.
"A moist frontal system will approach the B.C. South Coast this evening then stall through Friday, giving an extended period of rainfall," the weather agency cautions.
"Heavy downpours can cause flash floods and water pooling on roads …Localized flooding in low-lying areas is possible. Watch for possible washouts near rivers, creeks and culverts."
Motorists are being urged to drive to conditions, and everyone in the region is advised to monitor alerts and forecasts.
