Remnants of tropical storm Debby merging with another low pressure system over the Great Lakes could bring up to 120 millimetres of rain to parts of Eastern Canada on Friday. A person holding an umbrella crosses Wellington Street as rain falls in Ottawa, Friday, Aug. 9, 2024. THE CANADIAN PRESS/Justin Tang

MONTREAL - Remnants of tropical storm Debby doused a large swath of Eastern Canada on Friday, with forecasters saying up to 120 millimetres of rain would fall in some parts of Quebec before it moved out of the region.

The storm merged with another low-pressure system over the Great Lakes and moved across southern Ontario and Quebec, prompting Environment Canada to issue alerts and warnings for communities between Cornwall, Ont., and Quebec City about the risk of flash flooding.

More than 150 millimetres fell in Montreal on Friday, surpassing the normal total precipitation for the month of August. Environment Canada said the rainfall broke the all-time daily record in the area of 152 millimetres, set on Nov. 8, 1996.

The rain was expected to end in Quebec by Friday night, with a few scattered showers remaining into Saturday, said Environment Canada meteorologist Michèle Fleury.

The heavy rain forced the closure of some attractions in the province, including Montreal's La Ronde amusement park and the Granby Zoo, east of Montreal. The opening events scheduled for the International de montgolfières, a hot-air balloon festival in St-Jean-sur-Richelieu, southeast of Montreal, were postponed until Monday. All tennis matches scheduled for Friday at the National Bank Open in Montreal were postponed.

Montreal Pride announced it was postponing outdoor activities including community day in the Village and the Soirée 100 per cent Drag at Montreal's Olympic Park's esplanade, now taking place Saturday. "Tropical storm Debby won’t stop us from celebrating our pride!" organizers wrote.

One Montreal non-profit day shelter, Résilience Montréal, reported flooding at their offices. The organization's founder, Nakuset, took to social media to ask for help. The centre serves 1,000 meals a day.

“If you can come and help us, please do so,” she wrote on the X social media platform.

Nicholas Minas, a convenience store owner in Montreal's Parc-Extension neighbourhood, said he would be checking the store's basement for flooding before doing the same in his garage and his mother's basement, all of which have been inundated during previous heavy rains.

“I have to go downstairs and check every so often just because you never know when it’s going to happen,” said Minas. “When it comes, it comes down and you can see that the sewers don’t necessarily suck it up fast enough.”

Minas said he would welcome more so-called sponge parks, like the one a few blocks from his business, and any other solutions that can keep water out of his basement. The parks are designed to catch and absorb rainwater and keep it from flowing into overburdened sewers during heavy rain.

Stéphane Brossault, who heads Montreal's urban development water services division, told reporters Friday that the six sponge parks in the city were helping keep the streets of Montreal a little bit drier.

“The more water you see, the better,” he said, pointing to a pool of water retained in the lower sections of a local park “The goal of these parks is to catch water that would normally go into the sewer.”

However, amid reports of some flooded basements in the city, Brossault stressed that infrastructure cannot completely absorb the quantity of rain that fell in Montreal Friday over a short period. “The city is putting in place all it can to limit, to protect, but after a certain point you have to look at how to protect your building,” he said.

Quebec's Transport Department warned of some flooding on highways and temporary road closures due to the torrential rain. Most of the incidents of localized flooding were in and around north-central Montreal. Provincial police said they were in touch with various partners regarding weather conditions, but did not report any major traffic accidents linked to the inclement weather.

Ottawa received about 76 millimetres as of Friday evening. In Toronto, between 25 and 50 millimetres of rain was expected.

The remnants of Debby were expected to reach New Brunswick by evening and dump 40 to 60 millimetres of rain through Saturday morning.

At least eight people have died in the United States related to Debby. On Friday, it lashed parts of rural New York and Pennsylvania as it made its way up the U.S. Northeast, leaving intense flash flooding in its wake.

Debby was downgraded to a tropical depression late Thursday afternoon, and was a post-tropical cyclone on Friday, the U.S. National Hurricane Center said. It made landfall early Monday on Florida's Gulf Coast as a Category 1 hurricane and made a second landfall early Thursday in South Carolina as a tropical storm.

This report by The Canadian Press was first published Aug. 9, 2024.

— With files The Associated Press.

News from © The Canadian Press, 2024