Updated

The National Hurricane Center has issued the first hurricane watch for the outer islands of North Carolina as Hurricane Irene marches toward the U.S. coast.

Early Thursday, the center said Irene is approaching the northwestern Bahamas as a Category 3 storm with maximum sustained winds at 115 mph but the storm could become a category 4 hurricane by Thursday.

The head of the National Emergency Management Agency in the Bahamas said he received what he calls disturbing initial reports of damages from two southern islands that were some of the first to be hit as the storm approached the archipelago.

Capt. Stephen Russell tells The Associated Press that at least two settlements have been devastated on Acklins and Crooked islands. Russells says an official there reports that 90 percent of the homes in the settlements have been severely damaged or destroyed. Several hundred people live on each island. No injuries have been reported.

Forecasters say Irene's winds could increase quickly over the next day as the storm moves farther on its path toward the U.S.

Hurricane and tropical storm watches will likely be required for parts of the southeastern U.S. coast by early Thursday, but officials in North Carolina's coastal Dare County have already ordered as many as 150,000 tourists to leave beginning that morning.

Meanwhile, the U.S. Navy order the Second Fleet to prepare to move ships out of Irene’s path. The Navy said that the order applies to ships in southeastern Virginia, home to the largest naval base in the world.

The Navy says Irene's current track shows destructive winds and a dangerous storm surge are predicted to hit the area.

Federal officials have warned Irene, which has grown considerably more powerful since Tuesday, could cause flooding, power outages or worse all along the East Coast as far north as Maine, even if it stays offshore. The projected path has gradually shifted to the east, though the storm is still expected to make landfall as a major hurricane in North Carolina sometime over the weekend. It is then expected to continue trudging northward.

Irene was roared its way across the entire Bahamas archipelago Wednesday, knocking down trees and tearing up roofs and posing the most severe threat to the smallest and least populated islands, officials said.

Bahamian Prime Minister Hubert Ingraham said there have been no major injuries or deaths according to preliminary reports he has been receiving from throughout the widely scattered islands. But he added that they would not know the full extent of damage from the Category 3 storm until it is clear of the country on Friday.

In the Dominican Republic, flooding, rising rivers and mudslides have prompted the government to evacuate nearly 38,000 people. Authorities said a 40-year-old man was killed when floodwaters destroyed his home in Cambita, about 42 kilometers west of Santo Domingo, and a 42-year-old Haitian migrant drowned in a surging river near the city of El Seibo.

The evacuation in North Carolina on Wednesday was a test of whether people in the crosshairs of the first major hurricane along the East Coast in years would heed orders to get out of the way.

The first ferry to leave Ocracoke Island arrived just before 5:30 a.m. in nearby Hatteras with around a dozen cars on board.

It won't be easy to get thousands of people off Ocracoke Island, which is accessible only by boat. The 16-mile-long barrier island is home to about 800 year-round residents and a tourist population that swells into the thousands when vacationers rent rooms and cottages. Tourists were told to evacuate Wednesday. Island residents were told to get out on Thursday.

Currituck County officials have also asked visitors to think about leaving.

It wasn't clear how many people on the first arriving ferry Wednesday morning were tourists, but the first two cars to drive off it had New York and New Jersey plates.

Getting off the next ferry about an hour later was a family that included newlywed Jennifer Baharek, 23, of Torrington, Conn. She and her husband, Andrew, were married Monday and planned to spend their honeymoon on the island.

"We just got to spend one day on the beach and then we went to bed early to get up for the evacuation," she said.

The White House is urging people living in the path of the hurricane to follow the advice and warning of state and local officials as the storm approaches.

White House spokesman Josh Earnest said President Obama was briefed Wednesday on the latest developments. He said the Federal Emergency Management Agency is also coordinating with state and local officials.

The storm could impact Martha's Vineyard, the island enclave off the Massachusetts coast where Obama is vacationing. The White House said there are no plans at this point to change Obama's scheduled Saturday return to Washington.

In North Carolina, the state-run ferry service off Ocracoke Island would be free during the evacuation, but no reservations were allowed. Boats can carry no more than 50 vehicles at a time.

The island is part of North Carolina's Outer Banks, a roughly 200-mile stretch of fragile barrier islands off the state's coast. Pristine beaches and wild mustangs attract thousands of tourists each year. Aside from Ocracoke, the other islands are accessible by bridges to the mainland and ferries. The limited access can make the evacuation particularly tense.

All the barrier islands have the geographic weakness of jutting out into the Atlantic like the side-view mirror of a car, a location that's frequently been in the path of destructive storms over the decades.

In South Carolina, meanwhile, officials are not planning any evacuations in advance of Irene because forecasts show the storm is likely to miss much of the state's coast.

Gov. Nikki Haley said Wednesday that residents should still keep an eye on the weather and cautioned that people on the coast near the North Carolina line should still take precautions. But, she said that "after a long night of waiting" and watching forecasts, she determined the National Guard also no longer need to be on standby.

Irene is "going eastward and upward and that is what we wanted," she said.

Haley said warnings will be issued if the storm track changes in coming days.

The governor says officials in South Carolina coastal counties should be able to handle any issues brought by the storm and pledged to help North Carolina, where predictions show the storm could have a greater effect.

Irene has already wrought destruction across the Caribbean, giving a glimpse of what the storm might bring to the Eastern Seaboard. In Puerto Rico, more than a million people were without power, and one woman died after trying to cross a swollen river in her car. At least hundreds were displaced by flooding in the Dominican Republic, forced to take refuge in schools and churches.

It's been more than seven years since a major hurricane, considered a Category 3 with winds of at least 111 mph (179 kph), hit the East Coast. Hurricane Jeanne came ashore on Florida's east coast in 2004.

On North Carolina's mainland, residents who have weathered years of storms took notice. People flocked to gas stations and stores to stock up on supplies like gasoline for generators, plywood for boarding up windows, flashlights, batteries and drinking water.

In the coastal city of Wilmington, Tommy Early watched Tuesday as customers came in to his Shell service station to prepare. Irene was the main topic of conversation there, and Early was getting ready to give the hurricane its rightful place in a thick yellow notebook, even if it takes a turn out to sea. For years, Early has tracked names, wind speeds, rainfall and other data from storms that are nearly as familiar there as beach-loving tourists.

"Hurricane Earl," Early said Tuesday, looking up the entry for the storm that narrowly missed North Carolina last year. Evacuations also were ordered last year ahead of Earl. "That was a Category 4 at one point. One hundred and sixty mile-an-hour winds. We got lucky that time."

The last hurricane to hit the U.S. was Ike in 2008. The last Category 3 or higher to hit the Carolinas was Bonnie in 1998, but caused less damage than other memorable hurricanes: Hugo in 1989, Floyd in 1999 and Isabel in 2003.

Though a Category 2, Isabel cut a new inlet through Hatteras Island and killed 33 people.

At Craft American Hardware at Wrightsville Beach, Don Korman said he had placed a big order set to arrive Wednesday: Batteries, lanterns, tarps and shutter supplies.

"People are watching the TV, but they usually come by a few days before," he said. "If it looks like it's coming like this, you can run out of stock really quick."

Korman, though, plans to be ready even for eleventh-hour supply trips: the store is ready to plywood its windows and run off generator power until it becomes unsafe or unwise to keep the doors open.

"We won't close until the last minute," he said.

Most locals were heeding the warnings and getting ready for the storm, though few seemed panicked.

"Water, batteries, flashlights and now I'm going to get my grocery shopping done," said Sally Godwin, carrying two large jugs of fresh water out of Korman's store with her. "I live at the beach, and they always evacuate it the day before. I have to make sure all my little stuff's taken care of."

NewsCore and the Associated Press contributed to this report.