Hurricane Irma strengthened into a Category 4 storm as it inched closer to Florida, where hundreds of thousands are without power hours before one of the most powerful storms in the Atlantic hits.
Irma was 40 miles southeast of Key West early Sunday with winds of 130 mph, and is expected to pass Florida Keys between 7 a.m. and 8 a.m.
Its outer rain bands hammered the Florida Keys with whipping winds, heavy rain and powerful surges as it tore itself away from Cuba's northern coast.
"It's going from crappy to worse," said John Hines, who did not evacuate and stayed in his home in the Key West, at the southern end of the island chain that stretches off the tip of the Florida peninsula.
Hines said there's some flooding outside his house, but from the rain, not the storm surge.
"All the interior doors are starting to rattle now, sounds like someone is knocking on the front door," he said. " The winds are picking up. It's only going to get worse as it gets closer."
More than 288,000 customers lost power in the state, a majority of them in Monroe County, where Key West is, and Miami-Dade County.
Almost the entire state of Florida is under a hurricane warning affecting at least 36 million people, with concerns of devastating gales, heavy rain and life-threatening storm surge.
Hours earlier, the governor implored the 6.5 million Florida residents under mandatory evacuation orders to heed the warning.
"If you have been ordered to evacuate, you need to leave now. This is your last chance to make a good decision," Florida Gov. Rick Scott said Saturday.
Those who did not evacuate are in danger, Federal Emergency Management Agency Administrator Brock Long said.
"You're on your own until we can actually get in there and it's safe," he told CNN.
"The message has been clear: The Keys are going to be impacted. There is no safe area within the Keys. And you put your life in your own hands by not evacuating."
Irma has been catastrophic, killing 24 people this week in the Caribbean islands, where entire neighborhoods lay in ruins.
The major concern is the storm surge, which can cause devastating flooding and could reach as high as 15 feet in some areas, officials warned.
"You can't survive these storm surges," the governor said.
Key West business owner Jason Jonas said he stayed behind because his new home is "built like a bunker."
"It's pretty much the only reason I considered staying here because I knew that I had a pretty good chance of making it through this thing," he said.
"We're 30 plus feet above sea level and in a place that's built to withstand 225 mph winds -- I mean that's a better chance than being exposed out on the highway in traffic trying to make it to Georgia."
Mass evacuations have sent throngs onto jammed highways heading north and created a severe gas shortage in some parts the state.
Irma hit Cuba's Ciego de Avila province late Friday as a Category 5 hurricane before it weakened. Waves as high as 23 feet were recorded, and bigger ones remained a possibility as it plodded west, officials said.
Here are the latest developments:
-- Hurricane warnings were extended north along Florida's west coast as far away as Perry. They include Florida Keys, Fernandina Beach and Lake Okeechobee.
-- A storm surge warning wraps around the state, from Brevard County to Tampa Bay.
-- More than 72,000 people have moved into more than 390 shelters across the state, the governor's office said.
-- As Irma barrels toward Florida, as many as 26 million people in the Dominican Republic, Haiti and Cuba could be exposed to destructive winds and torrential rain, the Red Cross said. Hurricane warnings were still in effect Saturday for parts of central Cuba.
-- At least 24 deaths have been blamed on Irma in the Caribbean islands, where it hit fast before marching toward Florida.
Other cities will feel storm's punch
Florida cities such as Naples, Sarasota and Tampa are in or near the forecast path of the storm's eye.
Storm will be devastating for central Florida, Tampa, Fort Myers, Naples and Key West, CNN meteorologist Chad Myers said.
Tampa Mayor Bob Buckhorn said a storm surge is the main fear.
"We're going to get through the winds, we'll get through the rain, depending on what the level of surge is," he said. "But more importantly, the surge will occur tomorrow at the same time we have a high tide -- so that compounds the problem."
In Fort Myers, where storm surge warnings are in effect, Evanson Ngai stayed up all night, tracking the hurricane.
"I've tried to get some sleep but I can't. Just the nervousness, trying to keep an eye on it to see if its track will change," he said.
Ngai plans to crouch in the bathtub when it makes landfall.
"Right now, it's a little bit of gusty winds and some rain," he said early Sunday. "We've moved everything away from windows. We're hoping for the best -- we've bought nonperishable foods and water, and we have a flashlight."
Florida Power and Light estimated 3.4 million of its customers could be without power at some point during Irma, the company's largest number of outages ever.
"We think this could be the most challenging restoration in the history of the US," company spokesman Chris McGrath said.
Other states may be affected
Officials in other states are also keeping an eye on Irma. South Carolina Gov. Henry McMaster issued a mandatory evacuation for some barrier islands, while Georgia Gov. Nathan Deal expanded the state of emergency to include 94 counties.
The National Weather Service in Atlanta issued a tropical storm watch for the area Monday and Tuesday. Schools in the state planned to close Monday.
Alabama and North Carolina may also be affected, FEMA said.
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