The GTA and much of southern Ontario got a drenching Sunday as a powerful summer storm moved through the region.

Environment Canada issued a severe thunderstorm warning for Toronto and most of the GTA Sunday ahead of heavy rains and hail that pounded the region.

The storms were part of a fast-moving system that set off tornado warnings in southwestern Ontario and brought down trees over homes and cars in Grand Bend.

“It certainly developed really rapidly, but we were anticipating some severe weather,” Environment Canada’s Jason Vurford told CP24.

Vurford said 50 millimetres of rain had been measured at G. Ross Lord Dam.

The heavy rainfall prompted a warning from the Toronto and Region Conservation Authority.

“Thunderstorms in the GTA produced over 50mm of rain in the last hour,” the TRCA said on its Twitter page around 9:15 p.m. “Stay well back from rivers and streams tonight please. Be safe!”

Flooding reported

Pictures sent to CP24 from around GTA showed heavy rain and hail pounding the region.

At one location at Woodbine and Steeles avenues, a number of cars appeared to be half-submerged in a parking lot that resembled a lake after the downpour.

Toronto Fire Services also said they had responded to numerous calls related to the storm.

“We’ve had flooding in the northeast section of the city,” Toronto Fire, Cpt. Adrian Ratushniak told CP24.

He said firefighters had been called to help rescue people from flooded cars and bus shelters. They also received calls about flooded basements and people getting stuck in elevators because of power outages.

Toronto Hydro reported a power outage brought on by downed branches in North York at one point. Some 700 customers were affected by the outage, but it was resolved by around 10:30 p.m.

Travel affected

Several highway onramps and offramps had to be shut down around the GTA as well, with the OPP reporting flooding near Highway 404 and Steeles Avenue and Highway 404 and Highway 7.

“We’re experiencing some extreme weather all through the region,” OPP Sgt. Kerry Schmidt told CP24 Sunday evening. “There are lots of weather conditions around us that are affecting traffic.”

He advised motorists to avoid travel if possible and not to try and drive through standing water as that could cause vehicles to stall.

“If you don’t have to go through standing water, please avoid it at all costs,” Schmidt said.

He also advised motorists to drive according to conditions.

The storm also affected air travellers, with Pearson International Airport advising travelers to check their flight status before heading to the airport. Information on the airport’s website showed that dozens of flights were cancelled.

By 11: 30 p.m., all of the watches and warnings had ended for the province.

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