About 2,000 people were left without power in northern Louisiana, nearly 100 homes were dark in Mississippi, and 72 were without power in southern Arkansas near El Dorado as of 1 a.m. local time (2 a.m. ET), utility Entergy reported.
A Delta Air Lines flight headed to Newark from Paris was also diverted to Boston because of the "King Kong like" turbulence they encountered as it approached Logan International Airport, according to NBC New York. Two people were taken to hospital.
A woman was also injured when trees came down on her house in Sterlington, La., according to NBC affiliate KTVE.
There were also reports of a tornado touching down near Roscoe, and as much as two inches of rain fell in the San Antonio region Wednesday, the NWS said.
While the chance of tornadoes is lower for Thursday, according to Michael Palmer, the lead meteorologist at The Weather Channel, the wacky weather is not over.
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"Going forward into Friday and Saturday the tornado threat goes up," he said. "Kansas, Oklahoma, Texas and parts of the southern plains will definitely go up. On Saturday the lower Mississippi Valley, Arkansas and other parts of the south east could be affected."
Elsewhere temperatures were lower than average but the thunderstorms that hammered parts of New York, New Jersey and Connecticut, would subside, he said.