Hurricane Dorian continued to strengthen and shift Saturday as forecasters said it was on course to get closer to Florida than previously forecast but still make landfall in Georgia and the Carolinas.

Grand Bahama and the Great Abaco Islands could take a direct hit Sunday night as the Category 4 storm continued to gain power, said NBC News meteorologist Bill Karins

Officials in the Bahamas were urging residents to evacuate areas most at risk.

“Homes, houses, structures can be replaced," the prime minister of the Bahamas said Saturday. "Lives cannot be replaced.”

Tourists vacationing in the Bahamas were sent to government shelters set up in schools, churches and other buildings offering protection from the storm as residents evacuated.

In Florida, Gov. Ron DeSantis warned residents of his state to remain vigilant, cautioning that the hurricane could change course again and bring dangerous storm surges and flooding even if it does not make landfall there.

“As you’re looking at these forecasts, a bump in one direction or the other could have really significant ramifications in terms of impact,” the governor said at a Saturday morning news conference.

Dorian's maximum sustained winds increased to nearly 150 miles per hour with even higher gusts, which brings it close to a Category 5 storm, defined as having winds 157 miles per hour or higher.

The northwestern Bahamas are expected to start feeling the effects of the hurricane as early as 2 a.m. Sunday, officials said.

"On its present track, it’s expected that the islands of Abaco and Grand Bahama will be seriously impacted by Hurricane Dorian on Sunday, Sunday night and into Monday," said Jeffrey Simmons of the country's meteorology agency. "This is a very strong and dangerous hurricane."

About 73,000 people and 21,000 homes are at risk, with a potential storm surge of 10 to 15 feet, the country's prime minister, Hubert Minnis said.

To put that into perspective, Minnis said, "I am 6-foot-1, surges will be two to three times my height."

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“Heavy rains, capable of life-threatening flash floods are expected over portions of the Bahamas and coastal sections of the southeastern United States this weekend through much of next week,” the National Hurricane Center said Saturday.

Authorities said they closed airports in the Abaco Islands, Grand Bahama and Bimini, but Lynden Pindling International Airport in the capital of Nassau would remain open.

A man constructs storm shutters before the arrival of Hurricane Dorian on the Great Abaco island town of Marsh Harbour, Bahamas, Aug. 31, 2019. Dante Carrer / Reuters

Dorian strengthened to a potentially devastating Category 4 storm Friday evening as it continued to churn in the Atlantic Ocean on course to the southeastern United States early next week.

The National Hurricane Center announced early Saturday that "there's been a notable change overnight to the forecast of Dorian after Tuesday" with its veering away from Florida, but the stressed that the shift does not rule out the possibility of the storm making landfall on the Sunshine State's coast.

"It’s important to stress that this doesn’t paint Florida as out of the woods yet," said Kathryn Prociv, a meteorologist for NBC News. "Florida is still very much in the red zone."

By Saturday night, NBC News forecaster Karins said, one outlying computer simulation showed the possibility of landfall near Daytona Beach. A key to Florida's fate is how far west Dorian moves before stalling in the Atlantic, he said.

If the storm spins west of Freeport, the Bahamas and the West Palm Beach, Florida, area will get more than just a glancing blow early next week, Karins said, and the hurricane could rake much of Florida's east coast.

After the system stalls and moves ashore — coastal Georgia, South Carolina and North Carolina are the expected landfall zones for now — residents could see Category 1 or 2 impacts early to midweek, he said.

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Dorian will continue westward through the weekend but is then forecast to turn northward as it approaches the east coast of Florida early next week, the center said. It will bring "risks of life-threatening storm surge, devastating hurricane-force winds, heavy rainfall and flooding along its path."

The latest forecast track has narrowed the "Cone of Concern," as Miami-Dade County no longer faces the threat of the center of the hurricane. Parts of Broward County, including Fort Lauderdale, remain in the possible path of a Dorian landfall, according to the center.