Florida's governor is warning residents to expect storm surges of up to 12 feet in some areas that will inundate houses.
Governor Rick Scott urged anyone living in an evacuation zone in southwest Florida to leave by noon Saturday as the threat of Hurricane Irma shifted west.
He says the storm is "going to go faster than you are."
Scott said 25,000 people in Florida have already lost electricity as Irma's outer bands began hitting the southern part of the state. He also warned of dangerous storm surge of between 6 feet (2 metres) and 12 feet (4 metres) across parts of Florida that "will cover your house.
The U.S. National Hurricane Center says the eye of Hurricane Irma is expected to hit southwest Florida and Tampa sometime Sunday, but the entire state will feel the storm's effects.
Hurricane Center spokesperson and meteorologist, Dennis Feltgen, says that while Miami won't get the core of Irma it will still get life-threatening hurricane conditions.
The Category 4 storm pounded Cuba early Saturday with maximum sustained winds of 130 mph (215 km/h). It was expected to strengthen before hitting Florida.
Meantime, France has dispatched one of its most impressive military transport planes to assist recovery efforts near the hurricane-battered French overseas islands of St. Martin and St. Bart.
In a statement Saturday, the French army said the four-engine airlifter A400M took off from the mainland city of Orleans to the Caribbean with a Puma helicopter, a dozen military and technical personnel and humanitarian cargo. U.S. officials are also working to secure some of the nation's most contaminated toxic waste sites as Hurricane Irma bears down on Florida.
U.S. officials are also working to secure some of the America's most contaminated toxic waste sites as bedfore Irma bears down on Florida.