WILMINGTON/FAYETTEVILLE (North Carolina) • Rising floodwaters threatened communities across the Carolinas yesterday as storm Florence hit the US north-east with heavy rain and tornadoes, after killing at least 32 people.

Widespread flooding has already reached roofs, turned highways into rivers and left thousands to be saved by rescue workers.

Waterways were expected to keep rising yesterday in places like Fayetteville, North Carolina, a city of 200,000 in the southern part of the state, according to the National Weather Service (NWS).

At least 32 people have been killed since Florence came ashore as a hurricane last Friday, including 25 in North Carolina and six in South Carolina.

One person was killed when at least 16 tornadoes developed from Florence on Monday in Virginia, where dozens of building were destroyed, the NWS reported.

The dead included a one-year-old boy swept from his mother as they tried to escape from their car amid floodwaters. The woman had driven around barricades to reach a closed road, the sheriff's office in Union County, near North Carolina's border with South Carolina, said on Facebook.

"Flooding is still going to be a concern into the weekend and into next week," NWS meteorologist Hal Austin said, noting there is a chance of rain for the region today.

With 1,500 roads closed across North Carolina, fire and rescue crews were waiting to go into many areas to assist with structural damage after Florence dumped up to 91cm of rain on the state since Thursday. "Road conditions are still changing," the North Carolina Department of Transportation said on Twitter yesterday. "What's open now may become impassable."

All told, more than 8 trillion gallons of rain fell on North Carolina, NWS said.

Forecasters warned that heavy rain could cause flash flooding in the US north-east yesterday. As much as 15cm of rain was possible in parts of the region, the NWS said. The storm was expected to keep producing heavy rain over Pennsylvania into southern New England.

Thousands of rescues have taken place in the Carolinas and more than 650 people were taken to safety in and around Wilmington, North Carolina, said Ms Barbi Baker, a spokesman for New Hanover County. The city took a direct hit when Florence came ashore and has been largely cut off since then due to storm surges and flooding from the Cape Fear River.

Property damage from the storm is expected to total at least US$17 billion (S$23.3 billion) to US$22 billion but that forecast could be conservative depending on further flooding.

REUTERS