The storm is headed to the southeastern coast of the U.S. with winds as high as 115mph.
Hurricane Dorian continues to strengthen in the Atlantic Ocean, with winds increasing up to 115 mph, making Dorian a Category 3 hurricane on the Saffir-Simpson scale. Hurricanes that are Category 3 or higher are considered major hurricanes.
Dorian is located 625 miles east of West Palm Beach Florida and moving northwest at 10 mph.
The slow march and rising intensity of the storm, which is moving in a northwestern direction to the Bahamas, has alarmed forecasters who worry parts of Florida will be walloped by strong winds, a storm surge and heavy rain for an extended period.
"I think there’s a pretty high degree of certainty that this is going to be a major hurricane," Florida Governor Ron DeSantis told a news conference from the state emergency operations center in Tallahassee. He said residents should prepare for a "multiday event."
Two thousand National Guard troops will have been mobilized for the hurricane by the end of Friday, with another 2,000 joining them on Saturday, Florida National Guard Major General James Eifert said.
Florida is under a declaration of emergency. In neighboring Georgia, Governor Brian Kemp has declared a state of emergency in 12 counties to assist with storm readiness, response and recovery.
Dorian is also expected to bring a life-threatening storm surge and flash flooding to the northwestern Bahamas, the Miami-based National Hurricane Center (NHC) said in its latest advisory at 11 a.m. (1500 GMT).
"Almost everyone has left, or is leaving today,” said Pauline Powell, 26, who was on a family vacation at the Island Seas Resort in Grand Bahama when the storm started barreling toward the area's pristine beaches.
The Bahamas Ministry of Tourism and Aviation said hotels and resorts throughout that part of the island nation have activated hurricane response programs, which typically include boarding up beach-facing windows and encouraging guests to leave.
The Grand Bahama International Airport in Freeport will close Friday night and will not open until Sept. 3, the ministry said in a statement.
Dorian began on Friday over the Atlantic as a Category 2 hurricane but was expected to strengthen and become a Category 3 later in the day. It had maximum sustained winds near 110 miles per hour (175 km per hour), according to the latest NHC advisory.
If, as expected, Dorian reaches Category 4 strength over the weekend, its winds will blow at more than 130 mph (210 kph). It is currently moving at a pace of 10 miles per hour (16 km/h), giving it more time to intensify before making landfall.
Forecasters predicted it will be near the Florida peninsula late on Monday.
They expect a storm surge of as much as 10 to 15 feet (3 to 4.5 meters) above normal in some coastal waters of the Bahamas and Florida, and rainfall of about 6 to 12 inches (15 to 30 cm), with up to 18 inches (46 cm) in some areas.