Thousands of people ignored calls to evacuate last week, and clung on in the dangerously exposed islands during the storm.
Teams are still working to clear Highway 1, the road connecting most of the inhabited islands, and bridge inspections are continuing.
The US aircraft carrier Abraham Lincoln has arrived off Florida and other navy ships were in the area on Tuesday to help distribute food to the Keys and evacuate residents.
In Jacksonville, Mayor Lenny Curry said 356 people had to be rescued amid record-high storm surges and flooding, the Florida Times-Union reported.
Media captionAerial footage shows the damage to homes in Orlando, Florida
Other parts of the state escaped the storm lightly compared to the Caribbean islands.
“The storm surge flooding in Miami is a mere fraction of what would have happened if the core of the storm had been further east,” Rick Knabb, former director of the National Hurricane Center, said in a tweet.
Another hurricane, Jose, has been weakening over the western Atlantic, with swells due to affect parts of Hispaniola (the island split into Haiti and the Dominican Republic), the Bahamas, and the Turks and Caicos Islands, later this week.