Tornadoes damaged homes, destroyed a fire station, briefly trapped people in a grocery store, and ripped the roof off an apartment complex in Mississippi, authorities said on Wednesday.
Meanwhile, two people died when a tree fell on their mobile home in Alabama.
The National Weather Service (NWS) had warned that as the storm front moved east from Texas, strong twisters capable of carving up communities over long distances were possible.
tornadoes fueled by record heat hit the US south
They were fueled by record-high temperatures and threatened a region of the United States home to more than 25 million people.
From Tuesday afternoon to Wednesday morning, 73 tornado warnings and 120 severe thunderstorm warnings were issued, according to Matthew Elliott, a meteorologist at the Storm Prediction Center in Norman, Oklahoma, as per The Guardian.
A suspected tornado damaged several homes in Hale County, where the emergency director stated that more than one-third of the residents live in highly vulnerable mobile homes.
Russell Weeden of WBRC said, "I've seen some really nice mobile homes tied down, but they just don't stand a chance against a tornado."
According to Clay Bennett, sheriff of Caldwell Parish, Louisiana, two people were injured when the storm tore apart houses.
The National Weather Service confirmed that tornadoes touched down in Mississippi.
Images of the wreckage in Caledonia showed a grocery store damaged, a fire station shredded, and a house toppled, but Cindy Lawrence, the county emergency director, told WTVA-TV that no one was hurt.
Power lines were downed by high winds, and flooding was a risk as more than 5 inches of rain fell in some areas in a matter of hours.
According to poweroutage.us, over 50,000 customers in Mississippi and Alabama were without power.
For several days, forecasters had warned of the possibility of tornadoes.
Elliott, who coordinates the warnings, said it took a lot of effort to get the word out while people were celebrating the holidays, but it appeared that people were taking the threat seriously.
Tornadoes wreak havoc on parts of Alabama
The National Weather Service estimated that the tornado that killed two people in the Flatwood area near Montgomery had winds of 110 mph.
Tornadoes are also thought to have caused damage in the state's western and southwestern regions, according to the service.
Late Wednesday, the weather service upgraded the tornado to an EF-2 with 115 mph winds.
The assessment noted that the update was based on a survey of significant tree damage and downed high-tension power lines in the area.
The roof of an apartment complex near Eutaw in Greene County was ripped off late Tuesday, exposing residents' rooms, according to a video from CNN affiliate WBMA.
According to WBMA, some displaced residents sought refuge at a middle school.
Joe Mays of Tallassee, Alabama, told CNN that he, his wife Ashley, and their three sons were asleep in their home when the severe weather phone alarms woke them up.
They only had enough time to change their clothes and figure out what was going on before the storm hit.
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