PITTSBURGH – A pair of storms that pounded Pittsburgh on Friday cut electricity to hospitals and universities and submerged more than a dozen vehicles in a flash flood that killed a woman and two children and left another person presumed dead.

Officials said drivers were overwhelmed as water rose up to 9 feet in some places along Washington Boulevard, which parallels the Allegheny River in the city’s Highland Park section.

Rescue crews used inflatable boats to reach marooned drivers, though some swam to safety on their own. Rhodearland “Bob” Bailey, of Penn Hills, who is about 80, was rescued from the roof of his car.

“I can swim a little bit and was looking at a tree branch,” Bailey told the Pittsburgh Tribune-Review. “I heard one woman yelling for help, but the water was coming down so fast, I couldn’t see. … I’ve never seen nothing like this in my life. Lord have mercy.”

The area received 2.1 inches of rain in an hour, said Rihaan Gangat, a meteorologist for the National Weather Service. But an earlier storm meant the region was drenched by 3 to 4 inches of rain overall on Friday.

The three victims, whose names were not released, were unable to escape their vehicle, which was completely submerged and pinned to a tree, Pittsburgh public safety director Michael Huss said at a news conference.

Rescuers floated over the car without knowing it was below.

“The bottom of the boat didn’t even scrape against the top of the car,” said Raymond DeMichiei, deputy director of the city Office of Emergency Management.

A fourth person, a 70-year-old woman, was missing and presumed dead.