The storm had lost some of its strength after hitting the Bahamas. But it intensified again into a Category 3 storm Wednesday night, with maximum sustained winds of 115 mph, according to the National Hurricane Center.
The city of Charleston was already experiencing flooding Thursday morning, Charleston County Emergency Management told CNN. Dorian is 80 miles south-southeast of the city, the National Hurricane Center said in a 5 a.m. advisory.
Dorian is expected to continue moving closer to coast of South Carolina throughout the day and then along or over the coast of North Carolina Thursday night into Friday, the National Hurricane Center said.
Mandatory evacuations in the Carolinas
More than 1 million people in parts of South Carolina and North Carolina are under mandatory evacuation orders, forecasters said.
The South Carolina cities of Charleston, North Charleston and Mount Pleasant are under a flash flood warning until 10:15 a.m. ET, the National Weather Service in Charleston said Thursday morning.
Hurricane Dorian is expected to bring between 15-20 inches of rain along the South Carolina coast through Thursday afternoon, including downtown Charleston, meteorologist Steve Rowley with the National Weather Service in Charleston office told CNN.
The storm’s eye wall is expected to pass less than 40 miles from the Charleston County coast, he said.
South Carolina Gov. Henry McMaster declared a state of emergency on Tuesday, and the hurricane center warned of “life-threatening storm surge and dangerous winds, regardless of the exact track of Dorian’s center.”
As conditions began to deteriorate in the city of Charleston early Thursday, emergency management officials requested that citizens shelter in place, the Charleston Police Department said on Twitter.
More than 106,000 customers were without power Thursday morning in South Carolina. Dominion Energy said 64,000 customers were in the dark along the South Carolina coast.
State, federal and local agencies at the State Emergency Operations Center are working together to prepare evacuation and recovery efforts in anticipation of Dorian, according to a tweet from the South Carolina Emergency Management Division.
Hurricane warning extends to the Carolina-Virginia border
A hurricane warning is in effect from north of the Savannah River up to the North Carolina-Virginia border.
In Georgia, Gov. Brian Kemp issued a mandatory evacuation order for six coastal counties.
“We need people to evacuate,” he said. “This is not a storm to mess with.”
A state of emergency has been declared for 21 Georgia counties.
More than 9,1000 customers along coastal Georgia were without power Thursday, with the bulk of the outages around the Savannah area, according to Georgia Power.
Virginia also declared a state of emergency Tuesday, expecting possible flooding, storm surge, damaging winds and prolonged power outages, the Virginia Department of Emergency Management said.
Dorian is expected to remain a hurricane over the next few days, the hurricane center said Thursday morning.
An unpredictable path
Although the state avoided a direct hit, three Florida residents died in incidents related to storm preparation, including a 55-year-old Ocoee man who fell while trimming trees around his house, local officials reported.
A second storm brewing
As Dorian spins along the southeastern US coast, another storm is churning in the Atlantic.
The storm is not expected to strengthen over the next couple days and, but could slowly intensify by the weekend, the hurricane center said.
CNN’s Eric Levenson, Joe Sutton, Athena Jones, Michelle Krupa and Monica Garrett contributed to this report.