STEINHATCHEE, Florida, Aug 30 (Reuters) - Millions of residents were evacuated or hunkered down in homes and bunkers as Hurricane Idalia made landfall in Florida's Big Bend region as an "extremely dangerous" Category 3 storm on Wednesday, and authorities warned a life-threatening storm surge was possible.
Drawing strength from the Gulf of Mexico's warm waters, Idalia was forecast to unleash destructive winds and torrential downpours that will cause coastal flooding up to 16 feet (4.88 m) deep.
"Don't put your life at risk by doing anything dumb at this point. This thing's powerful," Governor Ron DeSantis said at an early news briefing in Tallahassee that was interrupted for a few seconds by a power cut.
The NHC said Idalia made landfall at 7:45 a.m. EDT (1145 GMT) at Keaton Beach, an ocean-front community of 13,000 people in Taylor County, about 75 miles (121 km) southeast of Tallahassee, the state capital. It is located in Florida's Big Bend region, where the state's northern Gulf Coast panhandle curves into the western side of the Florida Peninsula.
"Don't put your life at risk by doing anything dumb at this point. This thing's powerful," Governor Ron DeSantis said at an early news briefing in Tallahassee that was interrupted for a few seconds by a power cut.
The NHC said Idalia made landfall at 7:45 a.m. EDT (1145 GMT) at Keaton Beach, an ocean-front community of 13,000 people in Taylor County, about 75 miles (121 km) southeast of Tallahassee, the state capital. It is located in Florida's Big Bend region, where the state's northern Gulf Coast panhandle curves into the western side of the Florida Peninsula.
But as of 7 a.m. EDT (1100 GMT) it weakened slightly, slipping into Category 3, with maximum sustained winds of 125 mph (201 km). Any storm reaching Category 3 or higher is considered a major hurricane.
Most of Florida's 21 million residents, and many in the adjacent states of Georgia and South Carolina, were under hurricane warnings and other storm-related advisories. State emergency declarations were issued in all three.
DANGER TO LIFE
"They're expecting some fatalities, so I don't want to be one of them," Rene Hoffman, 62, said as she prepared to leave her home in Steinhatchee, Florida. She owns a food stand that she secured to her husband's pickup truck to keep it from washing or blowing away.
Florida's Gulf Coast, southeastern Georgia and eastern parts of North and South Carolina could face 4 to 8 inches (10 to 20 cm) of rain through Thursday, with isolated areas seeing as much as a foot of rain (30 cm), the hurricane center warned.
Officials said the storm's most dangerous feature would be a powerful surge of wind-driven surf that is expected to flood barrier islands and other low-lying areas along the coast.
Surge warnings were posted for hundreds of miles of shoreline, from Sarasota to the sport fishing haven of Indian Pass at the western end of Apalachicola Bay. In some areas, the surge could rise as high as 16 feet (4.9 m), the NHC said.
"If you end up with a storm surge that even approaches 16 feet, the chances of surviving that are not great," DeSantis said. "You would need to be in a three-story building because it is going to rise very, very high.
Sparsely populated compared with the Tampa-St. Petersburg area to the south, the Big Bend features a marshy coast, threaded with freshwater springs and rivers, and a cluster of small offshore islands forming Cedar Key, a historic fishing village demolished in 1896 by a hurricane's storm surge.
At the White House on Tuesday, U.S. President Biden said he and Florida Governor Ron DeSantis, who is seeking the Republican nomination to challenge Biden in the 2024 presidential election, were "in constant contact" about storm preparations.
Biden was set to speak about the government's hurricane response efforts later on Wednesday.
Idalia grew from a tropical storm into a hurricane early on Tuesday, a day after passing west of Cuba, where it damaged homes, knocked out power, flooded villages and prompted mass evacuations.
It will be the fourth major hurricane to strike Florida in the past seven years, following Irma in 2017, Michael in 2018 and Ian, which peaked at Category 5, last September.
More than 40 school districts in Florida canceled classes, DeSantis said, and Tampa International Airport suspended commercial operations on Tuesday.
About 5,500 National Guard members were mobilized, while 30,000 to 40,000 electricity workers were on standby. The state has set aside 1.1 million gallons of gasoline to address interruptions to fuel supplies, the governor said.
In Sarasota - a city hard-hit by Ian last year - Milton Bontrager, 40, who runs a charter fishing service near Tampa, said his home was boarded up and stocked with food, water and a generator, and his boats were secure.
"I don't panic, I prepare," he said on Tuesday.
Reporting by Maria Alejandra Cardona in Steinhatchee, Florida, Marco Bello in Cedar Key, Florida, Joey Roulette in Tampa, Florida, Rich McKay in Atlanta, Nelson Acosta in Havana, Dave Sherwood in Guanimar, Cuba, Brad Brooks in Longmont, Colorado, Brendan O'Brien in Chicago and Nandita Bose in Washington; Writing by Steve Gorman; Editing by Gerry Doyle and Bernadette Baum