U.S. East Coast braces for hurricane-fed flash floods and record pounding rain

U.S. President Barack Obama has declared a state of emergency in South Carolina as unrelenting rain across the U.S. East Coast showed little sign of letup Saturday, with record-setting precipitation expected to prolong the soppy misery that has been eased only by news that Hurricane Joaquin is no longer a threat.

A flash flood warning was in effect in parts of South Carolina, where authorities shut down the Charleston peninsula to motorists.

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Several feet of water had caused vehicles to stall in downtown Charleston and water has inundated some homes and buildings in the area, according to the U.S.National Weather Service. At least 50 to 100 millimetresof rain had been expected by noon. Barbara Vaughn, a Charleston city spokeswoman, said several people were rescued from stranded cars there.

The Charleston Police Department has issued lists of dozens of street closings, and the city's historic district was almost entirely shut down. Parts of the market area had sandbags piled up to keep the floodwaters out.

Charleston Police Chief Greg Mullen told The Associated Press that officers are going door-to-door to advise residents to voluntarily evacuate areas that are at risk, he said.

"Where we normally are dealing with flooding for a few hours, we're dealing with it in days here, so it's going to be significantly different," Mullen said. "It's impacting much more of the city. We're seeing areas flood today that did not traditionally flood."

Obama ordered federal aid to supplement state and local response efforts, and he authorized federal agencies to co-ordinate disaster relief efforts, a White House statement said.

Historic rain levels

Elsewhere, coastal flooding remained a threat particularly in the Virginia Beach area and the Outer Banks of North Carolina. The weather service issued a warning for residents living along the coast to be alert for rising water. A combination of high water and high waves could result in beach erosion and damage to docks and piers.

The rain levels had the potential to be "life threatening and historic," the weather service said on its website.

Hurricane Joaquin moves northward

9 years ago

Duration 2:05

U.S. east coast is taking precautions as storm hits the Bahamas

Once the rain ends, the threat of flooding persists because the ground is too saturated to absorb water, meteorologists say. And high winds could bring down trees like the one that hit a vehicle near Fayetteville, N.C., killing a passenger.

The storm also has been linked to a drowning in Spartanburg, S.C.

Flood watches and warnings also are in effect in Delaware and parts of New Jersey, Maryland and Virginia.

However, the Carolinas will probably get the worst of it, including possible landslides in the mountains, experts said.

"It's going to be a slow-motion disaster," said meteorologist Ryan Maue of Weather Bell Analytics.

Hurricane Joaquin, no longer seen as a danger to the U.S. Atlantic Seaboard, continued on a path expected to keep it well off the U.S. coast.

"It looks like we dodged a bullet this time," New Jersey Gov. Chris Christie said amid street flooding at the Jersey shore, devastated by Superstorm Sandy nearly three years ago. "Let's keep our fingers crossed."

Forecasters warned that even as Joaquin peels away from the coast, its effects will be felt, because it will continue supplying tropical moisture to the gusty rainstorm stretching from Georgia to the northeastern New England states.

South Carolina could get more rain in three days than it normally gets during the entire fall.

Joaquin tore off roofs, uprooted trees and unleashed heavy flooding in the Bahamas, and the U.S. Coast Guard was still searchingfor a missing 224-metre cargo ship with 33 people aboard.