British Columbia

Metro Vancouver weather warning: flash floods possible

A wet weather system that dumped heavy rain and snow across southern B.C. early Wednesday morning is forecast to continue.

Flooding, freezes ahead; 100 mm of rain and 30 cm of snow forecast for some areas

Slush and snow greeted drivers on the Coquihalla Highway in B.C. on Tuesday. (Glen Kugelstadt/CBC)

A wet weather system that dumped heavy rain and snow across southern B.C. early Wednesday morning is forecast to continue.

Environment Canada is forecasting up to 75 mm of rain could fall in areas such as the North Shore and Fraser Valley by Thursday night.

Some mountain passes, including Allison Pass on Highway 3, saw whiteout conditions Tuesday, and officials with the Ministry of Highways say 27 cm of snow accumulated on Highway 6 through the Monashee Pass overnight.

At lower elevations in the Fraser Valley, residents have been warned to watch out for flash floods and water pooling on roads, particularly in Chilliwack and Abbotsford.

Drivers faced whiteout conditions on Hwy 3 at Allison Pass on Tuesday afternoon. (Drive BC)

Motorists are advised to check driving conditions before setting out.

A frontal system is expected to bring heavy rain and snow to southern areas of B.C. and Alberta on Tuesday and Wednesday. (CBC)

'Volatile week' in Vancouver area

In Metro Vancouver, Environment Canada said that Tuesday's heavy rain would be just the beginning this week.

"An active storm pattern over the Eastern Pacific Ocean will lead to a volatile week of weather ahead," it said.

Between 60 and 100 mm of rain is expected over low lying areas this week, with up to 150 mm possible on southwest-facing slopes. And with the heavy rain comes the possibility of flooding.

"With the ground already saturated, river levels are expected to rise in response to the rainfall. Rising temperatures may result in the melting of mid-elevation snow packs which would contribute to the runoff," Environment Canada said.

By Saturday, cold air from the north and strong outflow winds will cause below-normal temperatures and a blustery weekend.

El Niño predicted

Overall, West Coast residents should be expecting above average temperatures this winter according to CBC meteorologist Johanna Wagstaffe.

"NOAA still predicting a 58 per cent chance of an El Niño this winter, which typically means warmer winters for the Pacific Northwest," says Wagstaffe.

"While La Niñas do have a correlation with higher snowfall, El Niño doesn't necessarily mean less snow, and it doesn't look like it will be a very strong one either."

Across the rest of Canada colder than average temperatures are forecast for the winter ahead.