Florida faces the "most catastrophic” storm in its history as Hurricane Irma prepares to unleash devastating force on the state, including 120mph winds, life-threatening sea surges that could submerge buildings and an advance battery of tornadoes.
"You need to leave – not tonight, not in an hour, right now,” Governor Rick Scott commanded in a press conference, 12 hours before the cyclone was expected to make landfall on Sunday morning. "This is the most catastrophic storm the state has ever seen.”
The US national hurricane centre said in its 8pm Saturday update on Irma that "heavy squalls with embedded tornadoes” were already sweeping across south Florida. The US National Weather Service later said the first hurricane-force wind gust had been recorded in the Florida Keys, a low-lying island chain off the state’s southern coast.
Irma dropped to a category three hurricane but could regain its category four intensity as the bathtub-warm seawater of nearly 32C (90F) will enable the storm to build strength.
It was forecast to hit the Keys first, then again near Cape Coral or Fort Myers, and then a third time near Tampa Bay on its path up Florida’s west coast. Weather stations in Marathon, a city in the Keys, reported sustained winds of 51mph (81kmh) with a gust to 71mph (115kmh) on Saturday night.
In Florida’s south-west, officials expected sea surges as high as 15ft (4.5 metres), which can rapidly rise and fall.
"Fifteen feet is devastating and will cover your house,” Scott said. "Do not think the storm is over when the wind slows down. The storm surge will rush in and it could kill you.”
He said at least 76,000 people were without power as the 350 miles (560km) wide storm unleashes winds and rain on the state. Officials said the window for people in evacuation zones was shutting, with gas stations closing and bridges blocked off.
More than seven million people were ordered to flee their homes in several states, including nearly a third of Florida’s population. Around 50,000 people were in 300 shelters around the state, counties enacted curfews and power providers have already begun to struggle with demand.
In Miami, Guardian reporter Richard Luscombe was sheltering with his family in a 5ft x 5ft interior closet with no windows, away from exterior walls and doors.
"My mobile phone has been screaming its high-pitched alarm every 10 minutes over the last hour or so with dire warnings from the National Weather Service to take cover NOW because of tornadic thunderstorms in the area,” he said.
"The threat of tornados comes from thunderstorms in Hurricane Irma’s violent outer bands, which have been circling over Miami-Dade and Broward counties for most of the day as the storm moves ever closer.
"It’s likely to be a long night in the closet with the kids.”
Donald Trump was monitoring the progress of the storm from the presidential retreat in Camp David, Maryland where he held a cabinet meeting.
In Palm Beach, Trump’s waterfront Mar-a-Lago estate was under evacuation order.
"This is a storm of enormous destructive power, and I ask everyone in the storm*s path to heed ALL instructions from government officials,” Trump said on Twitter.
Forecasters said the tropical cyclone would maintain hurricane strength well into Georgia on Monday.
It leaves behind a trail of devastation in the Caribbean, with 25 confirmed killed, including 11 people on French St Martin and St Barts, four in the US Virgin Islands, three on Puerto Rico, two on Dutch St Maarten, one person in Anguilla and a two-year-old in Barbuda.
Its most recent victim, Cuba, experienced 125mph (200kmh) winds on Saturday that damaged hotels in the island’s best-known beach resorts and forced evacuations as far along the coast as low-lying areas of the capital Havana.
Power was out and mobile phone service was spotty in many regions as Irma, the first category five storm to make landfall on the island since 1932, passed over. The island’s communist government ordered the evacuation of more than a million people from its path.
In the fishing town of Caibarien, streets were carpeted with fresh green seaweed as the water receded, people said it was the strongest cyclone ever to hit the town.
Irma’s turn northward was expected to occur around 150 miles (240km) east of the capital. Nevertheless, authorities shut off power in large parts of the city and evacuated around 10,000 people from central Havana near the Malecon seawall because of fears of flooding from the storm surge.
By Saturday evening, the sea had penetrated two blocks over parts of the city’s historic seafront boulevard, and the waters were expected to advance further as the surge grew. Restaurants on the seaside drive pulled down their shutters and stacked sandbags.
The Caribbean islands will barely have time to take stock before category four Hurricane Jose threatens landfall, complicating relief efforts for islands that have only just emerged from Irma’s winds.
Jose spared Barbuda, where the prime minister estimated 90% of buildings were destroyed by Irma a few days earlier.
Although Jose is weaker and moving away from the Islands, high winds are likely to hit Peurto Rico and possibly Dominican Republic as soon as Sunday morning local time.
However, residents in the British Virgin Islands described a scene of "utter devastation” in the wake of Irma and pleaded for the UK government to send more food, water and shelter.
Natalie Drury, who lives with ehr husband in Tortola, said she was in a "state of disbelief” about the destruction left by the storm. Homes and businesses had been destroyed, she said, the streets were strewn with sewage and looters had emptied shops.
"We desperately need help as soon as possible. Food, water, shelter. I’m extremely concerned about health and safety – there is sewage absolutely everywhere.
"It’s worse than anyone could have imagined. The country is going to need some serious help. I have no idea how many people have died. We were told yesterday it’s gone up to 10, but obviously that’s all rumours. Nobody knows yet.”