Five-thousand members of the Florida National Guard have been activated to help during Hurricane Ian. Another 2,000 guardsmen from Tennessee, Georgia and North Carolina are also coming to help, Florida Gov. Ron DeSantis said.

Nearly 300 ambulances and support vehicles are being deployed to areas bracing for Ian’s landfall, DeSantis said.

-ABC News’ Alex Faul

In Tampa, where residents are bracing for 10 feet of dangerous storm surge, the Tampa International Airport may shut down parts of its airfield and facilities over the next day or two, airport officials announced.

The airport is in an evacuation zone, but because it’s critical infrastructure, it’s “exempt from the storm evacuation order and will stay open until a closure is necessary,” airport officials said in a statement.

It’s been 101 years since Tampa last had a direct hit from a major hurricane.

Hillsborough County Public Schools in Tampa will be closed Monday through Thursday due to the storm. Instead, some schools will operate as storm shelters, the district said.

In Sarasota County, schools will be closed on Tuesday.

NASA said it will roll the Artemis I rocket off the launch pad and back to the vehicle assembly building on Monday night due to the storm.

“Managers met Monday morning and made the decision based on the latest weather predictions associated with Hurricane Ian, after additional data gathered overnight did not show improving expected conditions for the Kennedy Space Center area,” NASA said in a statement. “The decision allows time for employees to address the needs of their families and protect the integrated rocket and spacecraft system.”

There is potentially major flooding in Orange and Seminole counties and St. Johns River, potentially up to Jacksonville in northeast Florida, Gov. Ron DeSantis said Thursday.

"The amount of water that's been rising and will likely continue to rise today, even as the storm is passing, is basically a 500-year flood event. And I know Seminole County has done evacuations, I know they've opened shelters, but we're gonna see a lot of images about the destruction that was done in southwest Florida and obviously we have massive assets there," DeSantis said.

"This storm is having broad impacts across the state and some of the flooding you're going to see in areas hundreds of miles from where this [storm] made landfall are going to set records. And that's going to obviously be the things that will need to be responded to," DeSantis added.

The damage caused by the storm will likely take years to repair, he said.

"You're looking at a storm that's changed the character of a significant part of our state. And this is going to require not just emergency response now, in the days or weeks ahead. I mean, this is going to require years of effort to be able to rebuild and to come back," DeSantis said.