Hurricane Dorian beat a steady path north on Wednesday, as residents of coastal South Carolina braced for the region's second-worst flooding in 85 years, authorities and forecasters said.

Dorian was on the move along the U.S. coastline early, lashing the east coast of central Florida and eyeing the Carolinas, where mass evacuations have already been ordered.

South Carolina appeared to be in line for some of Dorian's worst.

High tides are expected to top 9 1/2 feet on Wednesday afternoon and then 10 1/2 feet early Thursday morning, along Charleston Harbor, the National Weather Service said. Flooding occurs when tides reach 7 feet.

If Thursday's water levels come in at 10 1/2 feet, that would be the second highest in Charleston County history, topped only by the 12.52-foot tide that struck Sullivan Island in the midst of Hurricane Hugo on Sept. 22, 1989.

Since Monday afternoon, a 100-mile stretch of Interstate 26, from coastal Charleston to inland Columbia, has been running one way, west. That lane reversal will end at noon on Wednesday.

"Now is the time to leave," according to a statement Wednesday morning by the South Carolina Emergency Management Division.

Slow-moving Dorian has already devastated parts of the Bahamas where it killed at least seven people when it virtually stalled out over the northwestern islands.

Rain bands from the storm were drenching the northeastern coast of Florida at 5 a.m. Wednesday, the national hurricane center said. The storm is expected to come "dangerously close" to Florida's east coast and the Georgia coast through Wednesday night, and forecasters with the National Hurricane Center say it will move near or over the South and North Carolina coasts Thursday through Friday morning.

Though the storm is now a Category 2 with maximum sustained winds of 105 mph — it was a Category 5 when it made landfall in the Bahamas on Sunday — officials have warned residents to take precautions and to heed evacuation orders as it has the potential to produce storm surges of several feet.

Federal emergency declarations have been approved for four states — FloridaGeorgiaSouth Carolina and North Carolina — and the governor of Virginia had also declared a state of emergency.

The hurricane is expected to remain at about the same intensity for the next couple of days, and even if it does not make landfall, hurricane-force winds are expected to reach parts of the coast from central Florida to North Carolina, the hurricane center said.

The Latest on Dorian:

  • The hurricane was lashing the east coast of central Florida early Wednesday and was about 95 miles east-northeast of Daytona Beach and moving north-northwest at 8 mph.
  • The storm had maximum sustained winds of about 105 mph early Wednesday.
  • At least seven people have died in the Bahamas, and more deaths are expected to be reported, the prime minister said.
  • Officials said Dorian was set to move "dangerously close" to Florida's east coast and the Georgia coast through Wednesday night, and near or over the South and North Carolina coasts Thursday through Friday morning.

The forecast track of the hurricane continues to take it “dangerously close to the southeast U.S. coast,” the hurricane center said in a forecast discussion Wednesday morning.

“All interests from northeast Florida to the Carolinas should remain vigilant to the possibility of experiencing destructive winds, flooding rains, and life-threatening storm surges from this hurricane,” the center said.

The center of Hurricane Dorian was around 100 miles east of Daytona Beach on Wednesday morning, and video showed winds and rain hitting parts of St. Augustine Beach, the coast southeast of Jacksonville, Cocoa Beach and more Tuesday night and Wednesday morning.

Volusia County, Florida, emergency management officials tweeted early Wednesday that all bridges there were closed to eastbound traffic. The county sheriff’s office said it was prepared with high-water rescue teams if needed.

Hurricane warnings were in place from a stretch of the Florida coast from Volusia-Brevard County line to Ponte Vedra Beach in Florida, and from the Savannah River on the Georgia-South Carolina border to Surf City, North Carolina, the hurricane center said.

Storm surge warnings stretched from a large section of the coast from Sebastian Inlet, Florida, south of Melbourne, to Surf City in North Carolina. The hurricane center said that storm surges of 5 to 8 feet could be seen in some parts of the Carolinas, and 3 to 5 feet in parts of Florida and Georgia.

On Wednesday morning, the National Weather Service issued a high-risk area for flash flooding over parts of South and North Carolina for Thursday, warning residents that "very heavy rainfall" totaling 15 inches is possible.

Whatever the exact tract that the hurricane takes in the coming days, "life-threatening storm surge and dangerous winds" are expected along parts of Florida’s east coast and Georgia and the Carolinas, the hurricane center said.

North Carolina Gov. Roy Cooper urged residents to take evacuation orders seriously. He activated 300 National Guard members and issued evacuation orders for all barrier islands beginning Wednesday.

"We have seen the life-and-death effects of this storm in the Bahamas, and we urge everyone on the islands at the coast to leave," he said in a statement.

The governors of South Carolina and Georgia have also ordered at least 1 million people to evacuate. Authorities in Florida ordered mandatory evacuations in some vulnerable coastal areas.

While there have been no recorded deaths as a result of storm conditions in the U.S., at least two people have died while making preparations in the last few days.

A 55-year-old man died Monday after falling some 15-foot from a tree in Ocoee, Florida, the fire brigade said. The man, who was not named, was rushed to hospital but later pronounced dead.

"He was in a tree cutting limbs in preparation and then a limb broke lose," said Corey Bowles, spokesperson for the Ocoee Fire Department. "He was preparing for the storm."

On Sunday, a 68-year-old David Alan Bradley, from Indialantic, Florida, died after falling from a ladder on his third-story balcony, police said.

He was putting plywood on his windows, Indialantic Police Chief Michael Connor confirmed in an email early Wednesday.

Separately, a 61-year-old man died while swimming in the Atlantic Ocean near Hatteras Village, North Carolina on Sunday, the National Park Service said.

The service said the cause of death was unknown but that a high risk of rip currents were forecast for most of the beaches along the Hatteras National Seashore on Sunday. It was unclear if the man had been caught up in a rip current.

Some 823 flights within, into and out of the U.S. were so far cancelled early Wednesday and Daytona Beach, Orlando and Palm Beach international airports are among those that remain closed due to weather conditions, according to FlightAware, an aviation data company.

As the U.S. braces for Dorian, the Bahamas has begun to assess the scope of the disaster there. For hours, Dorian parked over Abaco and Grand Bahama Islands, pounding them with winds up to 185 mph and torrential rain before finally moving into open waters Tuesday on a course toward Florida.

“It’s total devastation. It’s decimated. Apocalyptic,” Lia Head-Rigby, who helps run a local hurricane relief group and flew over the Bahamas’ hard-hit Abaco Islands, told the Associated Press. “It’s not rebuilding something that was there; we have to start again.”

Seven deaths have been reported, but leaders say more are likely. Head-Rigby said her representative on Abaco told her there were “a lot more dead,” though she had no numbers as bodies being gathered.

The Bahamas’ prime minister also expected more deaths and predicted that rebuilding would require “a massive, coordinated effort.”

“We are in the midst of one of the greatest national crises in our country’s history,” Prime Minister Hubert Minnis said at a news conference. “No effort or resources will be held back.”

Cruiseline Royal Caribbean International announced Monday that it would commit $1 million to disaster relief efforts to help rebuild the island nation.