Gov. Ron DeSantis said there is "significant damage" throughout the Big Bend region, with Columbia, Madison and Dixie counties hardest hit.

"There is, of course, a lot of debris to clean up. But we will get working with that with the local communities to make sure that the roads are cleared and people can go back to their lives," DeSantis said during a press briefing.

As of 6 p.m. there is one unconfirmed fatality due to the storm involving a traffic incident that the Florida Department of Law Enforcement is reviewing, the governor said.

"That may end up being a confirmed fatality, it has not been confirmed yet," DeSantis said.

Thirty of the 52 school districts that closed due to the storm will reopen Thursday, and an additional eight will reopen on Friday, the governor said.

-ABC News' Hannah Demissie and Will McDuffie

Idalia is forecast to be a tropical storm as it reenters the Atlantic Ocean on Thursday, tracking away from the U.S.

Storm surge will continue to be a threat due to the circulation of tropical storm Idalia, with the winds bringing water ashore.

Heavy flooding rain will also continue tonight.

A tornado watch remains in effect until 10 p.m. for the Carolinas.

-ABC News' Kenton Gewecke and Melissa Griffin

More than 485,000 customers are without power across four states in the wake of Hurricane Idalia.

That includes more than 260,600 customers in Florida and more than 210,200 in Georgia.

More than 14,000 customers in the Carolinas are also impacted.

Idalia has weakened from a hurricane to a tropical storm as it slams Georgia and the Carolinas with rain and wind.