Rainfall warning issued for Metro Vancouver as 1st storm in powerful trio expected tonight

Environment Canada has issued a rainfall warning for Metro Vancouver, as the first in a trio of powerful October storms is set to hit British Columbia's South Coast tonight.

An even more intense storm is coming Saturday as the remnants of Typhoon Songda make landfall, Environment Canada warns.

The potential is there for Saturday's wind and rain to rival the storm in August 2015 that knocked out power to half a million B.C. Hydro customers, said meteorologist Matt MacDonald, of Environment Canada.

"It's a little bit of a scary looking storm," he said.

Tonight, in contrast, the South Coast is in for more of a "textbook-like" fall storm, said MacDonald. A second storm is expected Thursday night to Friday, with the whopper hitting on the weekend.

"At this time, it looks like each storm will become more intense," Environment Canada said in a statement covering the following areas:

• Metro Vancouver — rainfall warning.
• Fraser Valley, including Chilliwack and Abbotsford.
• Vancouver Island.
• Southern Gulf Islands.
• Sunshine Coast.
• Howe Sound.
• Whistler.

Rainfall warning tonight

Light rain will begin this evening, becoming quite heavy overnight with five to 10 millimetres likely every hour between 2 a.m. and 8 a.m. PT in Metro Vancouver.

In total, the first storm is expected to bring rainfall of up to 60 millimetres along the North Shore mountains.

Rain is expected to ease or stop completely on Thursday morning, with rain and strong winds coming back by Thursday night.

"Heavy downpours can cause flash floods and water pooling on roads," Environment Canada warns.

'Widespread damage' expected Saturday

Saturday's storm is expected to bring a lot of rain, as is common with remnants of typhoons, said MacDonald.

"This is the peak of typhoon season, so it isn't rare to see the remnants of typhoons. But to see them intensify is exceptional."

If the storm materializes as expected, officials are warning residents to be prepared for power outages, flooding, downed trees and possibly even landslides. BC Hydro has deployed additional crews to Vancouver Island, the Gulf Islands and the Sunshine Coast in anticipation. 

• B.C. storms: Here's how to prepare

"We'd likely see widespread wind damage across the Lower Mainland and Vancouver Island," said MacDonald.

The River Forecast Centre has issued a high streamflow advisory for all of Vancouver Island, and say there is the possibility of flood conditions on Saturday and Sunday, particularly in the central part of the island.

Strong winds are expected to exceed 80 km/h over exposed coastal areas. However, the winds are expected to come from the southeast, which is often less damaging in this region than other directions.

Rainfall is also expected to be heavy and may exceed 200 millimetres for the western and inland regions of Vancouver Island for the four-day period.

It could top 100 to 150 millimetres for Metro Vancouver, climbing to 300 millimetres in the North Shore mountains.

Grouse Grind pre-emptively closed

Local and regional governments in the Lower Mainland have begun making preparations for the storm.

Metro Vancouver will be closing all trails in the Lower Seymour Conservation Reserve as of 8 p.m. PT because of the weather, and the Grouse Grind will be closed effective October 13. 

The municipality of Delta will also be closing beach assess points and installing flood protection berms, and TransLink is warning that SkyTrain lines could be shut down if winds exceed 100 km/h. 

Ken Brown, the City of Vancouver's manager for streets, traffic and electrical, says crews have been doing preventative maintenance the last two days in anticipation of the storms. He says a particular concern is the impact leaves could have.

"Since the leaves haven't all come off the trees yet, there's the potential for the leaves to fall and plug up the catch basins," he says.

"We're asking residents to preventative maintenance on their property ... if they do have excess leaves on their property, put them in the green bin, if they have more than the bin can take, then bag the rest, and they'll get picked up on their regular pick up. 

"We've been out all week checking our storm basins and inlets to our culverts making sure they're clear of debris," said Fiona Dercole, public safety manager for the District of North Vancouver, who was out with crews installing sandbags today.

"We have 35 creeks that run through our municipality...those creeks are prone to flooding in extreme weather events."