People look at damage after a tornado struck the Christ Community Church on April 3 in Paducah, Kentucky. The storm system is “set to stall for the next few days as a building upper-level ridge over the Southeast keeps it stationary,” per the National Weather Service. Photo: Michael Swensen/Getty Images

A powerful multi-day storm system that’s lashing the U.S. South and Midwest has killed at least seven people as it unleashes tornadoes and flooding flooding rains.

The big picture: The storm that ramped up Wednesday has brought a “life-threatening, catastrophic,” flash flood event to the Lower Ohio Valley and Mid-South. The National Weather Service said more “significant severe weather” was “expected from the Mid-South through the Ozarks and ArkLaTex,” with “very large hail and strong tornadoes possible.”

Parts, Tennessee, Kentucky and Arkansas were the most at risk for possibly widespread life-threatening flash flooding on the night of April 3 before the High Risk area shifts west slightly the following day. Screenshot: Nashville Fire Department, Tenn./ X

Structural damage at Christ Community Church after the tornado struck. The storm’s focus on April 3 has been the Lower Ohio Valley into the Mid-South and Lower Mississippi Valley. The storm High Risks of Excessive Rainfall (level 4/4) are in effect through April 6. Photo: Michael Swensen/Getty Images

Downed trees and heavy structure damage are seen after tornadoes moved through Selmer, Tennessee, on April 3. At least five people have died in storms this week in the state. Photo: Jason Davis/Getty Images

Floodwater from Whites Creek carries debris over a pedestrian bridge on the Fontanel greenway in Nashville, Tenn., where Axios Nashville reports flooding rains have inundated the city, resulting in temporary road closures.

Downed trees and heavy structure damage are seen on April 3 after tornadoes moved through Selmer. Photo: Jason Davis/Getty Images

A driver walks with a police officer after their car is swamped by standing floodwater beneath the B-Line Trail on West Third Street, Bloomington, Indiana, on April 2 during a torrential downpour from a severe thunderstorm that passed through the city. At least one storm-related death has been reported in the state. Photo: Jeremy Hogan/SOPA Images/LightRocket via Getty Images

The scene in Missouri, where at least one storm-related death has been reported. Whitewater Fire Protection District chief Garry Moore died after responding to a presumed tornado, per a Facebook post from the fire department. “Chief Moore observed a vehicle off the roadway and stopped to assess the incident and render aid if needed,” the post says. “A short time later, Chief Moore was found unconscious at the scene.” Screenshot: Missouri State Highway Patrol Troop F/X

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Editor’s note: This a breaking news story. Please check back for updates.