Hurricane Ian devastates US state of Florida. Aerial video shows devastated the Sanibel Island Causeway. #HurricaneIan #FortMyers #SanibelIsland #Florida #BBCNews #CNBCTV

Timelapse shows devastating storm surge 

from Hurricane Ian in Fort Myers, Florida

Aerial video shows Hurricane Ian 

devastated the Sanibel Island Causeway

"On Thursday morning, traffic crawled along a major road that slices the length of the Florida peninsula, with cars heading back towards areas hit hardest by Ian such as Fort Myers and surrounding Lee County. 

Almost all of this ocean-side county was without power as of 10:30 local time (15:00 GMT), authorities said, and search and rescue efforts were active. 

"I spend a lot of time studying hurricane damage, and I'm thinking it will be $100bn (£90bn) in damage and several hundred fatalities," said Hugh Willoughby, a meteorology professor at Florida International University. "I hope I'm wrong." 

Basic rebuilding and construction efforts will take until the new year, he said, though a full recovery to the area will take "several years". 

By Thursday afternoon, Ian had emerged over the Atlantic as it continues its journey west towards North and South Carolina. The US National Weather Service said it expects Ian to intensify into a hurricane once again. 

The warm water of the Gulf Stream - a fast-moving ocean current that travels north along the east coast of Florida - makes for ideal conditions for a hurricane, Professor Willoughby said. 

"Hurricanes derive their energy from warm ocean water and the Gulf Stream is sort of the warmest ocean water around," he told the BBC. 

But while the Carolinas are expected to be hit, they will likely face a weaker storm than Cuba and Florida have endured. "Unless we're very, very unlucky it won't be as intense as in Florida," he said." 

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