At least three men died in floodwaters in Louisiana, another person was missing after heavy rains pounded the state and the region was bracing for more wet weather in the coming days.
Part of Lake Charles, which was hit by two hurricanes just six weeks apart last year, got more than a foot of rain over 12 hours Monday, forecasters said.
Mayor Nic Hunter said hundreds of structures were flooded, but assessments were ongoing.
By Tuesday morning, more than 10 inches of rain had been recorded in Baton Rouge, according to the National Weather Service.
The confirmed weather-related deaths included a 33-year-old man who was found in a flooded vehicle after waters receded in Baton Rouge, and a 40-year-old man who was in a vehicle that crashed into a flooded canal in Port Allen, the state health department said.
Another person in the Toyota was believed missing, Louisiana State Police said.
In Lake Charles, a man was found dead inside a submerged vehicle, Charlie Hunter, chief investigator of the Calcasieu Parish Coroner's Office, said late Tuesday. His death was determined to be from flooding.
Alice Williams of Baton Rouge said the flooding came on fast.
"It started raining, and the rain got heavier and heavier. I looked outside, and the next thing I know my car was going underwater," Williams said Tuesday.
She was on the second floor of her building, but the first-floor homes were flooded. Tuesday she was taken from the area by boat. "It just happened so quickly," she said.
More rain is forecast for parts of Louisiana, including the Baton Rouge area and Lake Charles and southwest Louisiana.
An additional 4 to 6 inches of rain, was expected for Lake Charles through Thursday evening, and Lafayette could get another 4 inches.
It was almost nine months ago that Hurricane Laura made landfall in southwestern Louisiana on Aug. 27, followed by Hurricane Delta around six weeks later.
Flash flood watches covered most of Louisiana, eastern Texas, southern Oklahoma, and southwestern Arkansas on Tuesday evening.
Flash floods are likely across parts of Texas and in Louisiana through Thursday, according to the weather service.