High winds, heavy rain forecast for B.C. coast and islands bring potential for flooding

Wind and rainfall warnings cover much of the British Columbia coast on Tuesday as a wave of stormy weather washes over western parts of the province this week.

Environment Canada says winds gusting up to 110 km/h are expected over Haida Gwaii, the Central Coast and northern Vancouver Island.

Heavy rain is also forecast for Kitimat on the North Coast, as well as most of Vancouver Island and the Howe Sound region north of Vancouver.

Rainfall accumulations of 70 millimetres in Kitimat and more than 200 millimetres on western Vancouver Island are likely before the storm eases early Thursday and the weather office says localized flooding is possible, along with potential washouts near rivers, creeks and culverts.

Alyssa Charbonneau, meteorologist with Environment Canada, said the system is a narrow atmospheric river that will miss the Metro Vancouver area, where rainfall is expected to be heaviest on the North Shore, with levels diminishing eastward into the Fraser Valley.

"We do have a warning out for Howe Sound where we could see 50 to 70 millimetres of rainfall with this system. And parts of Metro Vancouver will likely see some good rainfall as well," she said.

Following a severe wildfire season, heavy rain could generate high surface water runoff and erosion, which could then lead to localized flooding and landslides, the B.C. government said in a statement. 

"It is important that everyone take steps to prepare for seasonal storms, regardless of where they are located in the province," reads the statement, which warns residents to stay away from riverbanks and prepare in case of floods.

The province notes, however, that widespread or severe impacts are not expected with the incoming storm system.

The River Forecast Centre has issued a high streamflow advisory for waterways on Vancouver Island, the Sunshine Coast and Howe Sound, warning of flows seen every two to five years.

An additional high streamflow advisory was posted for the North and South Thompson and Upper Columbia River basins in the Central Interior.

"Current weather modelling is indicating the potential for heavier rainfall rates (up to 50 mm) in areas around Revelstoke and surrounding areas to the west and east," reads the advisory.

A travel advisory has also been posted for Highway 4 east of Port Alberni, and road crews are watching carefully, as heavy rain could wash debris onto the road from the cliffs above, where a wildfire damaged trees and destabilized the soil earlier this year and caused extended road closures.