A US Coast Guard helicopter flies over a house destroyed by Hurricane Dorian in Bahamas on Thursday. AP

The howling west flank of Hurricane Dorian soaked the Carolinas on Thursday, flooding coastal towns, whipping up tornadoes and cutting power to hundreds of thousands of people a couple of days after it reduced parts of the Bahamas to rubble.

Dorian strengthens to Category 3 storm as it threatens US east coast

Dorian kills five in Bahamas US evacuates eastern coast

Floodwaters rose to a foot (30 cm) or more in low-lying parts of the historic South Carolina city of Charleston, where more than 7 inches (18 cm) of rain fell in some areas, officials said, with another half-inch or more expected overnight.

Among the few people in the streets as one of the largest Atlantic hurricanes ever recorded drew closer, were John Rivers, 74, and his three children. They cleared drains of branches, leaves and debris, using a shovel, a rake and bare hands.

A couple embraces on a road destroyed by Hurricane Dorian on Thursday. Ramon Espinosa/Associated Press

"We're giving the water somewhere to go," Rivers said, sheltering from the driving rain and gusts of wind under a covered walkway, while his daughter Caroline, 12, pulled off her rubber boots, pouring a stream of water from each.

"I see this as a good life lesson for my kids," Rivers said.

More than 260,000 homes and businesses were without power in South Carolina and Georgia on Thursday night, the tracking site poweroutage.us showed.

Dorian's eye was about 35 miles (60 km) southeast of Wilmington in North Carolina, with maximum sustained winds of 100 mph (160 kph), the Miami-based US National Hurricane Center said in its 8 p.m. advisory.

The center of the hurricane was forecast to move near or over the North Carolina coast on Thursday night and Friday, it said, adding that life-threatening storm surges and dangerous winds remained a threat for much of the area and Virginia.

People shelter inside a church after surviving Hurricane Dorian in Marsh Harbor, Bahamas. Brendan Smialowski/AFP

Governors in the region declared states of emergency, shut schools, opened shelters, readied national guard troops and urged residents to heed warnings, as media circulated fresh images of the storm's devastation in the Bahamas this week.

At least 70,000 Bahamians needed immediate humanitarian relief after Dorian became the most damaging storm ever to hit the island nation.

In the Carolinas alone, more than 900,000 people had been ordered to evacuate their homes. It was unclear how many did so.

In Kill Devil Hills, in North Carolina's Outer Banks, Mark Jennings decided to ignore the order, lining his garage door with sandbags and boarding up his home with plywood.

The retired firefighter planned to stay put with his wife and two dogs, saying, "We are ready to go. If something happens, we can still get out of here."

Dorian whipped up at least three tornadoes in the region, officials said. One in North Carolina damaged scores of trailers at a campground in Emerald Isle, but no one was injured, the News & Observer said.

Of at least four storm-related deaths reported in the United States, three were in Orange County, Florida, during storm preparations or evacuation, the mayor's office said.

In North Carolina, an 85-year-old man fell off a ladder while barricading his home for Dorian, the governor said.

Reuters