For more than a week - 8.5 days - Irma was a major hurricane, which Klotzbach says puts it second only to Hurricane Ivan in 2004 in the satellite era (which began in 1966).
Also as a result of the hurricane, at least three people have died in Georgia and at least another two in SC, said local media reports. Dennis Jones, director of the county's Emergency Management Agency, said in a Monday report.
After Irma's path of destruction cut through the Keys, residents in Islamorada who didn't evacuate came out to look at the damage.
"I didn't see the damage I thought I would see", he reported. After leaving the coast of Cuba, Irma had barrelled through the Florida Keys, a chain of low-lying islands to the south, on Sunday morning.
Several major airports in Florida that halted passenger operations due to Irma began limited service on Tuesday, including Miami International, one of the busiest USA airports.
Five deaths in Florida were blamed on Irma, along with two in Georgia.
So any criticism of Florida officials for taking the storm seriously and planning for all contingencies is misplaced.
The US National Weather Service said that Hurricane Irma is the strongest storm ever in the Atlantic.
"We got a flight to Jacksonville and I've been trying to find people to pick me up", she said. "As we rebuild, that will help GDP".
Federal and local authorities continue to conduct life-saving operations in the Keys and Jacksonville, where Florida experienced worst effects of the hurricane, Bossert added.
While Caribbean islands devastated by Irma are pleading for supplies, a huge U.S. government relief effort is under way to help Florida.
As of Monday morning, almost 60 percent of the entire state - close to 6 million customers - had lost electricity. The city's roads were scattered with downed power lines, making travel hard - even for authorities.
In South Carolina, a 57-year-old man was killed after a tree limb fell on him, while a 21-year-old died in a vehicle crash, said local officials.
It was still unsafe, with high winds reaching up to 50 miles (80 kilometers) per hour, heavy downpours and tornado threats in Georgia's southwestern region, according to the National Hurricane Center.
At 914 mb, Irma was the lowest pressure reached by an Atlantic hurricane outside of the western Caribbean and Gulf of Mexico on record, and was the lowest minimum central pressure since Hurricane Dean in 2007.