UPDATE 4-Strengthening Hurricane Florence blasts toward U.S. East Coast
Florence intensified into a hurricane on Sunday and is expected to strengthen rapidly as it churns across the Atlantic Ocean toward the U.S. East Coast, where it could make landfall by the end of the week.
With winds at 75 miles per hour (120 km per hour), Florence became a Category 1 hurricane and was expected to develop within a day into a major storm, defined as Category 3 or higher, according to the National Hurricane Center (NHC) in Miami.
"Make your plans now," South Carolina Governor Henry McMaster urged residents during a Sunday afternoon news conference. "Presume that a major hurricane is going to hit right smack dab in the middle of South Carolina."
Forecasters were also tracking two more storms further out in the Atlantic, with Tropical Storm Isaac expected to become a hurricane later on Sunday as it barreled toward the Caribbean.
On its current trajectory, winds from the hurricane could reach the southeastern United States late on Wednesday or Thursday, with Florence possibly making landfall around the Carolinas on Thursday or Friday.
The slow-moving storm system could further stall over the region, dumping rain and causing significant flooding, the National Weather Service said.
McMaster said he has asked U.S. President Donald Trump to declare a federal emergency in the state in anticipation of the storm's arrival.
"Everyone in North Carolina needs to keep a close eye on Florence and take steps now to get ready for impacts later this week," Cooper said in a statement on Sunday.
The storm's center was 750 miles (1,200 km) southeast of Bermuda at 11 a.m. EDT on Sunday. It was on track to move between Bermuda and the Bahamas on Wednesday, the NHC said.
Meanwhile, Tropical Storm Isaac, with maximum sustained winds of 65 mph (100 kph) on Sunday, was about 1,500 miles east of the Windward Islands, forecasters said. The forecast showed Isaac tracking south of Puerto Rico as it strengthened into a hurricane.
A third storm, Helene, off the Cabo Verde Islands was also expected to become a hurricane later on Sunday but did not appear to pose an immediate threat to land.