At least 10 people, including a mother and seven-year-old child, have been killed amid harsh weather in the US.
Storms and severe flooding have hit areas of Kentucky, leaving nine dead and hundreds of others in need of rescue.
Elsewhere, a person in Atlanta was killed when an “extremely large tree” fell on a home on Sunday, Atlanta Fire Rescue said.
Officials have warned the death toll is likely to rise as search and rescue efforts continue.
Kentucky governor Andy Beshear said: “This is one of the most serious weather events we’ve dealt with in at least a decade.”
Many of the deaths were caused by cars getting stuck in high water, he added.
The mother and child in the Bonnieville community were swept away on Saturday night, Hart County coroner Tony Roberts said. In Clay County, southeastern Kentucky, a 73-year-old man was found dead in floodwaters.
Larry Addington Field at Boyd County High School in Cannonsburg, Kentucky is now underwater. Pic via AP
Abandoned cars in floodwaters at a railroad underpass in Louisville. Pic: AP
Mr Beshear said: “So folks, stay off the roads right now and stay alive.
“This is the search and rescue phase, and I am very proud of all the Kentuckians that are out there responding, putting their lives on the line.”
US President Donald Trump has approved a request for disaster relief funding, he added.
The storms in Kentucky have left around 39,000 homes without power – and authorities have warned harsh winds could increase outages.
Parts of Kentucky and Tennessee received up to 15cm of rain over the weekend – and the effects will “continue for a while”, according to a senior forecaster.
Water rising along the Cumberland River in Clarksville, Tennessee. Pic: AP
Bob Oravec, from the US-based National Weather Service, said there are “a lot of swollen streams and a lot of flooding going on”.
“Any time there’s flooding, the flooding can last a lot longer than the rain lasts,” he added.
Much of the US is currently facing tough winter weather.
Over the weekend, avalanche warnings were issued for numerous areas of the Rocky Mountains as more than two feet of snow fell in parts of Colorado.
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A man struggles to remove snow from a driveway in Lewiston, Maine. Pic: AP
Bone-chilling cold is expected – with temperatures in northeastern Montana predicted to go as low as -42.7C (-45F) – while forecasters have warned a combination of heavy snowfall and wind gusts could create “hazardous whiteout conditions” in parts of New England and northern New York.
The National Weather Service warned of “life-threatening cold” into Tuesday.
Meanwhile, tornado watches have been issued in Georgia and Florida.