Atmospheric river system set to drench B.C.'s South Coast

Environment Canada is warning of an incoming atmospheric river weather system that will bring "prolonged heavy rain" to British Columbia's south coast this election weekend.

The weather agency says the "first significant storm of the season" is set to hit around noon Friday and last through Sunday, bringing up to 200 millimetres of rain, and a potentially soaking provincial election day on Saturday.

Ina special weather statement, it saidthe system will affect Metro Vancouver, the Fraser Valley, Howe Sound, Whistler, the Sunshine Coast and Vancouver Island, bringing up to 70 millimetres of rain in most areas, but up to 100 millimetres along coastal mountains and twice that on parts of the island.

Environment Canada says the heavy rain will be accompanied by strong winds, with gusts reaching 80 km/h close to the water.

WATCH | Atmospheric rivers, explained:

What is an atmospheric river?

2 years ago

Duration 1:23

It's a term that became more widely known after record-setting flooding hit B.C. in November 2021, but as meteorologist Johanna Wagstaffe explains, atmospheric rivers are not new to west coast of North America.

The agency is warning residents to beware of swollen rivers and creeks, increased risk of rockfalls and landslides, and power outages due to fallen trees.

It says the rain and wind are expected to ease by Sunday afternoon.

The River Forecast Centre has placed the South Coast, Central Coast, Vancouver Island and Lower Fraser tributaries under a flood watch, with high streamflow advisories for the North Coast and Interior mountains.

A flood watch is the second level on the provincial forecast centre's three-tiered warning system. It means that river levels are rising, and flooding in areas adjacent to riverbanks may occur.

Environment Canada also issued aspecial weather statementfor Fort Nelson,warning of snowbetween Friday and Sunday.

The statement says the region will experience its first "substantial" snowfall by the end of the week, with 10 to 20 centimetres expected.