Tor­na­does and vi­o­lent winds flat­tened homes and ripped apart build­ings from Ok­la­homa to In­di­ana in a se­ries of storms ex­pect­ed to bring record-set­ting rains and life-threat­en­ing flash floods across the na­tion’s mid­sec­tion in the com­ing days.

At least four peo­ple in west­ern Ten­nessee and Mis­souri were killed in the first wave on Wednes­day and ear­ly Thurs­day that spun off pow­er­ful tor­na­does, one launch­ing de­bris near­ly 5 miles (8 kilo­me­tres) above the ground in Arkansas.

Among those killed in Ten­nessee was a man in a home dam­aged by the storm near Moscow, about 50 miles (80 kilo­me­tres) from Mem­phis, said Ray Gar­cia of the Fayette Coun­ty Sher­iff’s Of­fice. Of­fi­cials were prepar­ing for more rain and strong storms on Thurs­day, he said.

“It looks like a swim­ming pool in my front yard,” he told The As­so­ci­at­ed Press.

Dozens of tor­na­do and se­vere thun­der­storm warn­ings were is­sued from Texas to West Vir­ginia.

Po­ten­tial­ly dead­ly flash flood­ing was al­so fore­cast for the South and Mid­west as se­vere thun­der­storms blow­ing east­ward be­come su­per­charged. 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 (30 cen­time­tres) 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. “His­toric rain­fall to­tals and im­pacts are pos­si­ble.”

Fore­cast­ers at­trib­uted the vi­o­lent weath­er to warm tem­per­a­tures, an un­sta­ble at­mos­phere, strong wind shear and abun­dant mois­ture stream­ing from the Gulf.

Wa­ter res­cue teams were be­ing staged across the re­gion and the Fed­er­al Emer­gency Man­age­ment Agency was ready to dis­trib­ute food, wa­ter, cots, gen­er­a­tors and meals.

More than 90 mil­lion peo­ple were at risk of se­vere weath­er across an area stretch­ing from Texas to Min­neso­ta and Maine, ac­cord­ing to the Ok­la­homa-based Storm Pre­dic­tion Cen­ter.

Tor­na­does touch down, and more could be com­ing

A tor­na­do emer­gency, the weath­er ser­vice’s high­est alert, was briefly de­clared around Blytheville, Arkansas, on Wednes­day evening, with de­bris loft­ed at least 25,000 feet (7.6 kilo­me­tres), ac­cord­ing to weath­er ser­vice me­te­o­rol­o­gist Chelly Amin.

The Arkansas Di­vi­sion of Emer­gency Man­age­ment re­port­ed dam­age in 22 coun­ties due to tor­na­does, wind gusts, hail and flash flood­ing.

Vol­un­teer fire­fight­ers and po­lice of­fi­cers in Lake City, Arkansas, searched through rub­ble and res­cued peo­ple overnight. Res­i­dents were with­out elec­tric­i­ty and some were al­so with­out wa­ter, May­or Cameron Tate said in a Thurs­day morn­ing Face­book post.

In far west­ern Ken­tucky, four peo­ple were in­jured while tak­ing shel­ter in a ve­hi­cle un­der a church car­port, said the emer­gency man­age­ment of­fice in Bal­lard Coun­ty. Mul­ti­ple build­ings and homes were bad­ly dam­aged from what ap­peared to have been a tor­na­do, the agency said.

Ware­house col­lapse is part of dam­age in In­di­ana

Two work­ers were in­jured on Wednes­day when the roof and a wall col­lapsed at a Sur La Ta­ble dis­tri­b­u­tion cen­tre in Browns­burg, In­di­ana, a com­pa­ny spokesper­son said in a state­ment.

Emer­gency crews worked for sev­er­al hours to free a trapped work­er there.

“It was just heavy de­bris that had fall­en on top of her,” Browns­burg Fire De­part­ment spokesper­son Kam­rick Hold­ing told WTHR-TV. “She hap­pened to be in the wrong place at the wrong time.”

The woman was con­scious and talk­ing dur­ing the res­cue. Her con­di­tion was not im­me­di­ate­ly known.

Five se­mi-trucks were blown over on In­ter­state 65 near Low­ell, In­di­ana, state po­lice re­port­ed.

At least 10 dis­tricts in In­di­ana can­celled or de­layed in-per­son class­es on Thurs­day. In­di­anapo­lis Pub­lic Schools an­nounced a re­mote learn­ing day due to pow­er out­ages at mul­ti­ple build­ings.

A tor­na­do touched down in the north­east­ern Ok­la­homa city of Owas­so on Wednes­day, ac­cord­ing to the weath­er ser­vice. There were no im­me­di­ate re­ports of in­juries, but the twister heav­i­ly dam­aged the roofs of homes and knocked down pow­er lines, trees, fences and sheds.

More than half a mil­lion cus­tomers in In­di­ana, Ohio, Ken­tucky, Arkansas, Ten­nessee, West Vir­ginia, Mis­sis­sip­pi, Mis­souri and Texas were with­out pow­er as of Thurs­day morn­ing, ac­cord­ing to Power­Outage.us, which tracks out­ages na­tion­wide.

Floods could in­un­date towns, sweep cars away

Ad­di­tion­al rounds of heavy rain were ex­pect­ed in parts of Texas, the low­er Mis­sis­sip­pi Val­ley and the Ohio Val­ley from mid­week through Sat­ur­day. Fore­cast­ers warned that they could track over the same ar­eas re­peat­ed­ly, pro­duc­ing dan­ger­ous flash floods ca­pa­ble of sweep­ing cars away.

Rain to­talling up to 15 inch­es (38 cen­time­tres) was fore­cast over the next week in north­east­ern Arkansas, the south­east cor­ner of Mis­souri, west­ern Ken­tucky and south­ern parts of Illi­nois and In­di­ana, the weath­er ser­vice warned, with some ar­eas in Ken­tucky and In­di­ana at an es­pe­cial­ly high risk for flood­ing.

As­so­ci­at­ed Press writ­ers An­drew De­Mil­lo in Lit­tle Rock, Arkansas; Adri­an Sainz in Mem­phis, Ten­nessee; Seth Boren­stein in Wash­ing­ton; Is­abel­la O’Mal­ley in Philadel­phia; Kathy Mc­Cor­ma­ck in Con­cord, New Hamp­shire; and Ed White in De­troit con­tributed to this re­port.