Hurricane Ian battered into Florida’s Gulf Coast with catastrophic force, unleashing howling winds, torrential rains and a treacherous surge of ocean surf that made it one of the most powerful US storms in recent years.

Crashing ashore as a Category 4 hurricane with sustained winds of up to 241 kph, Ian quickly transformed an idyllic stretch of sandy beaches and coastal towns into a disaster zone inundated by seawater.

Early video images of the storm’s fury on local TV and social media showed floodwaters sweeping away cars, nearly reaching rooftops in some communities and the ruins of homes as palm trees were bent almost in half.

Up to 76 cm of rain is forecast to fall on parts of central Florida as the storm moves inland, threatening to cause extensive flash floods.

Nearly 2 million homes and businesses statewide were without power as of an hour before sunset, utilities reported.

Residents were also trapped in their homes and vehicles, with rescuers unable to reach them, authorities said.

Warnings were issued against opportunistic people taking advantage of the misfortune to undertake looting.

https://twitter.com/Micahliu153/status/1575359236300804096

“This storm is doing a number on the state of Florida,” said Governor Ron DeSantis, who asked US President Joe Biden to approve a major federal disaster declaration providing a wide range of US emergency aid to the entire state.

US border authorities said 20 Cuban migrants were missing after their boat sank off the Florida coast as Ian neared the coast on Wednesday.

There were no immediate official reports of other storm-related casualties.

An unknown number of people were stranded in “high-risk” evacuation zones and in need of help after defying orders to seek higher ground, but rescue crews were unable to immediately reach them, the governor said.

Having swept past Cuba on Tuesday, leaving it without power for hours, Ian made landfall in Florida on Wednesday near Cayo Costa, a barrier island just west of Fort Myers, the US National Hurricane Center reported.

The storm’s peak wind speeds put it just shy of a Category 5 designation on the Saffir-Simpson scale, the maximum classification.

Ian then churned ashore on Florida’s mainland, south of the harbourside town of Punta Gorda, with slightly diminished winds.

DeSantis said Ian had generated life-threatening storm surges – waves of wind-driven seawater rushing in along the coast – of up to 3.7 metres in some places. Forecasters also warned of intense thunderstorms and possible tornadoes.

The sprawling, slow-moving storm pushed farther inland as darkness fell, and within six hours of landfall was downgraded to Category 2, with top sustained winds of 170 kmh.

Further weakening was forecast over the next day or so as Ian crosses the Florida peninsula on a northeasterly track, expected to reach the Atlantic Coast on Thursday afternoon.

The region around the landfall is home to miles of sandy beaches, scores of resort hotels and numerous mobile home parks, a favourite with retirees and vacationers alike.

Got this from a friend in #Naples – just so sad. ⁦@ActionNewsJax⁩ #Ian pic.twitter.com/HtC0CtG228

— Jason Brewer (@JasonNBrewer) September 28, 2022

The town of Fort Myers Beach was nearly submerged by floodwaters. A view of Sanibel Island posted on Twitter showed the ocean sweeping over a seawall into a resort hotel’s swimming pool. Another video from the island showed roads inundated by the storm surge, rising to the tops of street signs.

Even as Ian lashed the coast in the final hours before it swept ashore, authorities warned residents it was too late for anyone who had yet to evacuate to safely do so.

Most residents abandoned the area’s mobile home parks, taking refuge in local schools and other facilities converted to emergency shelters. The area’s numerous assisted-living facilities were mostly evacuated, too.

Climate change is making hurricanes wetter, windier and more intense. There is also evidence that it is causing storms to travel more slowly, meaning they can dump more rain in one place, scientists say.