The Veronica Mars star, filming her new movie in the USA city, was also left stranded by the storms.
With the arrival of what is potentially one of the most devastating storms to ever hit Florida, officials have set aside 3.2 million liters (0.85 million gallons) of water, filled 67 trailers with meals, and amassed 24,000 tarps.
Hurricane warnings in north and central Florida were downgraded to tropical storm warnings.
Officials in the Florida Keys have warned tourists and residents to stay away until further notice, noting: "The Keys are not open for business".
John Huston, who stayed in his Key Largo home, watched his yard flood even before the arrival of high tide. And crews worked to fix two washed-out, 300-foot sections of USA 1, the lone highway from the mainland, and check the safety of the 42 bridges linking the islands.
"Unable to move to the north and restricted from moving to the east by a developing upper-level high pressure, Jose should have no choice but to meander for a few days between Bermuda and the southeast US", he said. Florida Power and Light said it had "safely shut down" one of two nuclear reactors at its Turkey Point power plant. More than 100,000 customers were without power in Georgia and more than 80,000 in SC. Streets flooded, and flying objects such as coconuts turned into unsafe projectiles. Firefighters evacuated more than two dozen tenants in the pounding rain and wind.
Clearing roads: Roads are the main concern, Miami Mayor Tomas Regalado said, as thousands of trees are down.
But then Irma made a more pronounced westward shift that put a bull's-eye on the Tampa area - the result of what meteorologists said was an atmospheric tug-of-war between weather systems that nudged Irma and determined when it made its crucial right turn into Florida. The agency, though, said the pipeline bringing drinking water from the mainland "appears to be intact". But there is considerable damage - property damage, flooding from rainfall, and trees and power lines are down.
- In South Carolina, more than 177,000 customers were without power, according to utility companies.
Irma made its second USA landfall at Marco Island at about 3:30 p.m.
Lee County did not see the catastrophic storm surge that officials were bracing for. "All the beauty kind of got sucked out of the city".
"Florida evacuees should plan their return home very carefully", said Mark Jenkins, a spokesman for AAA - The Auto Club Group. And it could be a week until it's restored, Barnett said. Except for Pensacola, all of Florida's ports remain closed; Port Everglades and Port Tampa Bay have fuel tankers awaiting unloading, Gov. Rick Scott said earlier Monday. We have not seen any FPL crews.
"In the event of rising water, go up, not out", the sheriff's department added.
Flash flood emergency: The National Weather Service issued a flash flood emergency for parts of downtown.
"We are dealing with satellite phones and those landlines that are working to try to get information out", she said.
"I've been in Miami Beach for two years, which is prone to flooding, but this is completely out of the norm", Kiener told ABC News.