Tornadoes and violent storms struck parts of the South and Midwest on Wednesday, knocking down power lines and trees, ripping roofs off homes and shooting debris thousands of feet into the air as a swath of severe weather hit the region.

A tornado emergency was briefly issued in northeast Arkansas, with the National Weather Service’s office in Memphis, Tennessee, telling residents on the social platform X: “This is a life-threatening situation. Seek shelter now.” The emergency was lifted, though area residents remained under a tornado warning.

The South and Midwest also braced for potentially deadly flash flooding over coming days as severe thunderstorms blowing eastward become supercharged, forecasters warned.

The director of the Tennessee Emergency Management Agency issued a state of emergency Wednesday evening to mobilize state resources as the agency worked to respond to the severe storms, including anticipated flooding.

Dozens of tornado and severe thunderstorm warnings were issued in parts of Arkansas, Illinois, Missouri and Mississippi as the swath of storms hit those and other states Wednesday evening. Forecasters attributed the violent weather to daytime heating combining with an unstable atmosphere, strong wind shear and abundant moisture streaming into the nation’s midsection from the gulf. The potent storm system will bring “significant, life-threatening flash flooding” each day through Saturday, the National Weather Service said.

With more than a foot of rain possible over the next four days, the prolonged deluge “is an event that happens once in a generation to once in a lifetime,” the weather service said in one of its flood warnings. “Historic rainfall totals and impacts are possible.”

A tornado emergency was briefly declared around Blytheville, Arkansas, on Wednesday evening, with debris lofted at least 25,000 feet, according to Chelly Amin, a meteorologist with the weather service. This is the weather service’s highest alert and is rare, but it urges residents to seek immediate shelter. It was not immediately clear whether there were any injuries.

“It’s definitely going to be a really horrible situation here come sunrise in the morning in those areas, coming out of Arkansas,” Amin said.

A tornado was also reported on the ground near Harrisburg, Arkansas, on Wednesday evening, with the weather service telling residents on X to “be in your shelter NOW.”

In Pilot Grove, Missouri, several structures were damaged, cars flipped over and power poles snapped by a storm, said the state emergency management agency. Minor injuries were reported, according to the Missouri State Highway Patrol. Meanwhile, roads were closed because of storm debris and downed utility lines near the town of Potosi southwest of St. Louis, said the state transportation department.

Authorities in eastern Missouri were trying to determine whether it was a tornado that damaged buildings, overturned vehicles and tore down utility poles, tree limbs and business signs Wednesday morning in and around the city of Nevada.