At least 10 people have died as torrential downpours over the weekend drenched parts of the south-eastern US, submerging roads and houses.
Kentucky Governor Andy Beshear said nine people have died in his state, after making an emergency disaster declaration.
About 1,000 people stranded in flood waters had to be rescued, he also said on Sunday.
The same areas could now be affected by drier but colder conditions, and the risk of snow, ice and significant disruption – according to BBC forecaster John Hutchinson.
The other death over the weekend was in Georgia, where a man lying in his bed was struck by an uprooted tree that crashed into his home.
Kentucky, Georgia, Alabama, Mississippi, Tennessee, Virginia, West Virginia and North Carolina were under some type of storm-related alert over the weekend. Almost all of those states also suffered catastrophic damage in September from Hurricane Helene.
Hundreds of thousands of homes ended up without power – a number that reduced to tens of thousands early on Monday, according to monitoring site Poweroutage.us.
Some parts of Kentucky received up to 6in (15cm) of rain, National Weather Service (NWS) figures show, resulting in widespread flooding issues.
The rapid influx of rain caused river levels to rise quickly and trapped vehicles in feet of water, images posted online show. Hundreds of roads were closed.
Among those who died in the state were a mother and her seven-year-old child, and a 73-year-old man.
A resident of rain-lashed Knott County told CNN he was anxious he would “lose everything again”, as he was still rebuilding his home from devastating flooding two years previously. Danny Laferty told the broadcaster the type of flooding he had seen in recent years was “different”.
Beshear said that he had written to the White House requesting an emergency disaster declaration and federal funds for affected areas.
President Donald Trump approved the declaration on Sunday, authorising the Federal Emergency Management Agency (Fema) – which he has suggested abolishing – to co-ordinate disaster relief efforts.
In Obion County, Tennessee, heavy rains caused a levee to break, “resulting in rapid onset flooding”, according to an X account for the local National Weather Service (NWS) station.
The town of Rives along the Obion River, with a population of about 300 people, was deluged from the breached flood barrier. Footage showed brown water rushing over rocks and past trees, as rescue workers in red boats passed flooded homes.
Steve Carr, the Obion County mayor, declared a state of emergency himself, ordering mandatory evacuations in Rives. Meanwhile, West Virginia Governor Patrick Morrisey issued his own state of emergency in more than a dozen counties over the weekend.
Kristi Noem, head of the Department of Homeland Security (DHS), which oversees Fema, said she had been in contact with the governors of affected states.
“While emergency management is best led by local authorities, we reinforced that DHS stands ready to take immediate action to offer resources and support,” Noem said.
The same weather system is now bringing heavy snow to parts of Canada. Meanwhile, the NWS warns that arctic air could bring record-breaking cold and dangerous wind chills to the central US this week.
