Bahamian Prime Minister Hubert Minnis said Dorian was moving slowly, extending the islands' exposure to the storm
Hurricane Dorian powered toward Bahamas and the US coast of Florida with increasing fury on Saturday, becoming an "extremely dangerous" Category 4 storm but leaving forecasters uncertain whether it would make a direct hit on the state's east coast or inflict a glancing blow.
The storm's winds rose to 215 km/h and then, hours later, to a howling 225 km/h as Dorian gained strength while crossing warm Atlantic waters.
Tourists scrambled to leave the Bahamas as Hurricane Dorian approached its northwestern islands of Grand Bahama and Abaco, eager to take off before the international airport was to shut down.
Grand Bahama and Abaco are hubs for the Bahamas' thriving tourism industry. The archipelago nation owes nearly 30% of its direct gross domestic product and half of its jobs to the industry, Joy Jibrilu, director general of the Ministry of Tourism, said in an interview.
"Anything that could derail that is really very concerning," Jibrilu said.
The country is "still reeling" from Hurricane Matthew, which ripped into the Bahamas in 2016, she added, noting that some hotels took years to make repairs.
In a televised news conference, Bahamian Prime Minister Hubert Minnis said Dorian was moving slowly, extending the islands' exposure to the storm.
"This hurricane will produce catastrophic results," said Captain Stephen Russell, director of the National Emergency Management Agency (NEMA), as he urged residents of Abaco and Grand Bahama to accelerate storm preparations.
Locals were left to seal up their homes and businesses before the storm's expected arrival this weekend.
"We've been through it before, so we know how to prepare," said Grand Bahama chocolate shop owner Amanda Ormerod, who was busy storing paperwork, covering machinery and eating her perishable ice cream sandwiches.
Jibrilu of the Tourism Ministry stressed that guests do not need to leave the Bahamian capital of Nassau or nearby Paradise Island, which are not expected to experience hurricane conditions.
In 2017, the Bahamas tourism industry sagged when hurricanes Irma and Maria cut a deadly path across the Caribbean, though they largely spared the archipelago. The World Travel and Tourism Council said the two storms caused an estimated drop of 826,100 visitors across the region.
The hurricane could wallop the state with even higher winds and torrential rains late Monday or early Tuesday, with millions of people in the crosshairs, along with Walt Disney World and President Donald Trump's Mar-a-Lago resort.
Though Dorian is growing in intensity, some of the more reliable computer models predicted a late turn northward that would have Dorian hug the coast, the National Hurricane Center said.
"There is hope," Weather Underground meteorology director Jeff Masters said.
The faint hope came on a day in which Dorian seemed to get scarier with each forecast update, growing from a dangerous Category 3 hurricane to an even more menacing Category 4 storm. And there were fears it could prove to be the most powerful hurricane to hit Florida's east coast in nearly 30 years.
Late Friday, the National Hurricane Center's projected new track showed Dorianhitting near Fort Pierce, some 115 kilometres north of Mar-a-Lago, then running along the coastline as it moved north. But forecasters cautioned that the storm's track was still highly uncertain and even a small deviation could put Dorian offshore or well inland.
Trump declared a state of emergency in Florida and authorized the Federal Emergency Management Agency to coordinate disaster-relief efforts. He told reporters that "Mar-a-Lago can handle itself" and is more worried about Florida.
"This is big and is growing, and it still has some time to get worse," Julio Vasquez said at a Miami fast-food joint next to a gas station that had run out of fuel. "No one knows what can really happen. This is serious."
As Dorian closed in, it upended people's Labor Day weekend plans. Major airlines began allowing travelers to change their reservations without a fee.
The big cruise lines began rerouting their ships.
Disney World and the other resorts in Orlando found themselves in the storm's projected path.
With Dorian days away and its track uncertain, Disney and other major resorts held off announcing any closings, and Florida authorities ordered no immediate mass evacuations.
"Sometimes if you evacuate too soon, you may evacuate into the path of the storm if it changes," Gov. Ron De Santis said.
Homeowners and businesses rushed to cover their windows with plywood. Supermarkets ran out of bottled water, and long lines formed at gas stations, with fuel shortages reported in places. The governor said the Florida Highway Patrol would begin escorting fuel trucks to help them get past the lines of waiting motorists and replenish gas stations.
At a Publix supermarket in Cocoa Beach, Ed Ciecirski of the customer service department said the pharmacy was extra busy with people rushing to fill prescriptions. The gr ocery was rationing bottled water and had run out of dry ice.
"It's hairy," he said.
As of 0300 GMT, Dorian was centered about 605 kilometres east of the northwestern Bahamas.
That was also about 880 kilometrers east of West Palm Beach with the storm packing sustained winds of 225 km.h.
It was moving west-northwest at 17 km/h.
Forecasters warned that its slow movement could subject Florida to a prolonged and destructive pummeling from wind, storm surge and heavy rain.
Coastal areas could get 5 to 30 centimetres of rain, with 46 centimetres in some places, triggering life-threatening flash floods, the hurricane center said.
FEMA official Jeff Byard said Dorian is likely to "create a lot of havoc" for roads, power and other infrastructure.
Also imperiled were the Bahamas , where canned food and bottled water were disappearing quickly and the sound of hammering echoed across the islands as people boarded up their homes. Dorian was expected to hit by Sunday with the potential for life-threatening storm surge that could raise water levels 15 feet above normal.
"Do not be foolish and try to brave out this hurricane," Prime Minister Hubert Minnis said.
"The price you may pay for not evacuating is your life."
In Florida, the governor urged nursing homes to take precautions to prevent tragedies like the one during Hurricane Irma two years ago, when the storm knocked out the air conditioning at a facility in Hollywood and 12 patients died in the sweltering heat. Four employees of the home were charged with manslaughter earlier this week.
DeSantis said the timely message from those arrests is: "It's your responsibility to make sure you have a plan in place to protect those folks."
At NASA's Kennedy Space Center in Cape Canaveral, NASA moved a 380-foot-high mobile launch platform to the safety of the colossal Vehicle Assembly Building, built to withstand 200 km/h wind. The launcher is for the mega rocket that NASA is developing to take astronauts to the moon.
The hurricane season typically peaks between mid-August and late October. One of the most powerful storms ever to hit the US was on Labor Day 1935.
The unnamed Category 5 hurricane crashed ashore along Florida's Gulf Coast on September 2. It was blamed for over 400 deaths.