While torrential rains were expected to ease in flood-ravaged Louisiana on Monday, forecasters warned the threat was far from over.
Louisiana has been hit by a deluge of rainfall since last week, with at least five people dead and thousands of homes damaged by historic floods.
Louisiana Gov. John Bel Edwards said officials "won't know the death toll for sure for several more days."
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President Barack Obama on Sunday signed a disaster declaration for the state, freeing up federal aid to support recovery efforts in the affected areas.
Drone footage captured entire neighborhoods under waist-high muddy waters and cars completely submerged as boats cruised down the streets of Baton Rouge.
More than 20,000 people have been rescued from the floodwaters and over 12,000 remained in shelters Sunday night, according to Edwards.
"It's not over," he warned. "The water's going to rise in many areas. It's no time to let the guard down."
Edwards was himself an evacuee: chest-high waters filled the basement of the Governor's Mansion and cut off electricity, forcing him and his family to seek shelter elsewhere.
At least six rivers have hit record levels in Louisiana since the deluge began on Friday, according to The Weather Channel. It said the Amite River exceeded its previous record by over 6 feet in Magnolia.
One bit of brighter news for Louisiana is that the state won't see as much heavy rain on Monday, according to Weather Channel meteorologist Kevin Roth.
However, he explained that it'll be some time before the flood waters recede.
"The flooding isn't over because all the water that's upstream has to flow downstream," Roth said. "The river and the creeks will probably continue to rise.
Residents have fled to higher ground and neighbors with high-water vehicles have hit the flooded streets to help with rescue efforts. At least one hospital in the Baton Rouge area has evacuated critically-ill patients due to rising waters.
The National Guard and U.S. Coast Guard have been assisting in the response to the floods, using a variety of resources including helicopters to bring the stranded to safety.
Matthew and Rachel Fitzpatrick were brought to a church that had become a shelter by helicopter and told The Associated Press there were between 250 and 300 people still there Sunday.
"Everybody is just tired and nervous and wanting to see what kind of damage they have to their home," Rachel Fitzpatrick told The AP.
As Louisiana waited to dry out, forecasters warned the heavy rains that swamped the state were moving onward to Missouri and Illinois. Flash flood warnings were in effect for parts of those states on Monday.