At least four deaths were linked to the storm, including two people killed when trees fell onto homes in Florida and Alabama.
Forecasters warned that flooding could stretch into the Appalachians.
Isaias came ashore as a Category 2 hurricane Friday near Destin, Florida, a Gulf Coast vacation spot filled with high-rises and tourist shops.
The storm weakened overnight but remained dangerous.
Despite warnings of storm surges ahead of the storm, several major routes along the coast were open by daybreak Saturday and free of downed trees and power lines typically seen after major hurricanes.
Within the first hours after landfall, nearly 900,000 customers were without power, mostly in Florida and Alabama.
Hurricane-force winds in the Florida Panhandle blew the roof off a Pensacola hotel, and the city’s mayor said the airport “took some damage.”
The storm flattened a boathouse in Destin and ripped away part of the facade of a high-rise in Panama City Beach.
A worker in a condominium parking lot swept piles of the building’s insulation while others put back beach chairs that had been tossed about.
In Florida’s Escambia County, Sheriff Chip Simmons said a woman was killed when a tree fell on her home and a man died of carbon monoxide fumes from a generator running in his garage.
Four of the man’s family members, ranging in age from 4 to 72, were treated but expected to survive, the sheriff said.
Nearby in Gulf Breeze, Jayme Mitich wiped tears away Saturday as she surveyed the damage to her apartment.
Her living room was soaked and covered in insulation.
She and her 13-year-old daughter, Jeweliana Jackson, hid beneath a mattress before the storm tore off part of their roof.
“The noise got so loud, and I just kept hearing things break and crash into everything,” Mitich said.
The rest of their apartment complex was littered with roof shingles and broken beams from a wooden fence.
The winds uprooted trees and flipped a truck on its side.
“It’s going to be OK,” Mitich said.
“No matter what, we’re going to make it.”
Isaias, the first hurricane of the Atlantic season , roared farther into Alabama with tropical-force winds.
One person died when a tree fell on a house in Birmingham, said Cory Moon, the city’s fire chief.
A second storm-related death in Alabama was attributed to a motor vehicle crash involving a downed tree in Barbour County, said Josh Johnson of the state’s emergency management agency.
Along Alabama’s Gulf Coast, authorities in Mobile reported numerous downed trees and power lines.
Maranie Adams, who rode out the storm with her family and their chickens in Gulf Shores, Alabama, said the winds rocked their home, but it was nothing like Hurricane Sally, which left water under their elevated house.
“I feel very much more relieved today,” she said.
US President Donald Trump approved an emergency declaration for Georgia after earlier doing the same for Florida and Alabama, allowing for federal aid.
The US Energy Department authorised emergency exchanges of crude oil from the nation’s strategic petroleum reserve to address disruptions in supply because of the storm.
The Atlantic hurricane season has been unusually quiet this year, and Isaias was the first hurricane to hit the eastern US since 2024.
The National Weather Service advised that parts of Georgia and the Carolinas could see heavy rains capable of causing flash floods.
The storm was expected to move into the Tennessee Valley and then the mid-Atlantic on Sunday.
Meanwhile, in the Pacific, Simon strengthened into a Category 4 hurricane as it approached Mexico’s coast.
Simon was expected to bring heavy rainfall beginning Sunday to parts of southwestern Mexico with life-threatening flooding and mudslides.
Tropical Storm Rachel was also expected to bring heavy winds and rain to northern Mexico and Southern California over the weekend. (AFP)
