HOPKINSVILLE, Ky. — Torrential rains and flash flooding battered parts of the Midwest and South on Friday, killing a boy in Kentucky who was swept away as he walked to catch his school bus. Many communities were left reeling from tornadoes that destroyed entire neighborhoods and killed at least seven people earlier this week.

Forecasters warned of potentially catastrophic weather, with round after round of heavy rains expected in the central U.S. through Saturday. Satellite imagery showed thunderstorms lined up like freight trains over communities in Arkansas, Tennessee and Kentucky, according to the national Weather Prediction Center in Maryland.

In Frankfort, Kentucky, a boy died Friday morning after floodwaters swept him away while he was walking to a school bus stop, Gov. Andy Beshear said on social media.

The downtown area of Hopkinsville, Kentucky — a city of 31,000 residents 72 miles northwest of Nashville — was submerged. A dozen people and more than 40 pets had been rescued from homes as of the afternoon, a fire official said.

“The main arteries through Hopkinsville are probably 2 feet under water,” said Christian County Judge-Executive Jerry Gilliam. “So the mayor has closed downtown down for all traffic. Our office is actually in the middle of it, and we were here before the water rose. So there’s only one way we could get out.”

Tony Kirves and some friends used sandbags and a vacuum as they tried to hold back rising floodwaters that covered the basement and seeped into the ground floor of his photography business in Hopkinsville. Downtown was “like a lake,” he said.

“We’re holding ground,” he said. “We’re trying to maintain and keep it out the best we can.”

A corridor from northeast Texas through Arkansas and into southeast Missouri, which has a population of about 2.3 million, could see clusters of severe thunderstorms late Friday. The National Weather Service’s Oklahoma-based Storm Prediction Center warned of the potential for intense tornadoes and large hail.

The seven people killed in the initial wave of storms that spawned powerful tornadoes on Wednesday and early Thursday were in Tennessee, Missouri and Indiana. They included Garry Moore, chief of the Whitewater Fire Protection District in Missouri. He died while likely trying to help a stranded motorist, according to Highway Patrol spokesperson Sgt. Clark Parrott.

Tennessee Gov. Bill Lee said entire neighborhoods in the hard-hit town of Selmer were “completely wiped out” and it was too early to know whether there were more deaths as searches continued.

Heavy rains were expected to continue in parts of Missouri, Kentucky and elsewhere in the coming days and could produce dangerous flash floods capable of sweeping away cars.

In Hopkinsville, 5 to 8 inches of rain had fallen by Friday morning, causing the Little River to surge over its banks.

A pet boarding business was under water, forcing rescuers to move dozens of dogs to a local animal shelter, said Gilliam, the county executive. Crews rescued people from four or five vehicles and multiple homes, mostly by boat, said Randy Graham, the emergency management director in Christian County.

“This is the worst I’ve ever seen downtown,” Gilliam said.

Kentucky’s road conditions website showed scores of roads closed by high water, and a landslide closed a nearly 3-mile stretch of Mary Ingles Highway in the state’s north, according to the Kentucky Transportation Cabinet. A landslide closed the same section of road in 2019, and it reopened last year, WLWT-TV reported.

Flash flooding is particularly worrisome in rural Kentucky where water can rush off the mountains into the hollows. Less than four years ago, dozens died in flooding in the eastern part of the state.

Extreme flooding across a corridor that includes Louisville, Kentucky, and Memphis — which have major cargo hubs — could also lead to shipping and supply chain delays, said Jonathan Porter, chief meteorologist at AccuWeather.

Forecasters attributed the violent weather to warm temperatures, an unstable atmosphere, strong wind shear and abundant moisture streaming from the Gulf. At least 318 tornado warnings have been issued by the National Weather Service since this week’s outbreak began Wednesday.

Homes were ripped to their foundations this week in Selmer, which was hit by a tornado with winds estimated up to 160 mph, according to the weather service.

Tennessee Highway Patrol video showed lightning illuminating the sky as first responders scoured the ruins of a home, looking for anyone trapped.

In neighboring Arkansas, a tornado near Blytheville lofted debris at least 25,000 feet high, according to weather service meteorologist Chelly Amin. The state’s emergency management office reported damage in 22 counties from tornadoes, wind, hail and flash flooding.