In happier times, Interstate 4 from Tampa to Orlando is choked with pleasure seekers heading for the theme parks of Disney and similar enjoyable Florida pursuits. But on Tuesday, a deep sense of foreboding hung over the lengthy lines of near-stationary traffic as Hurricane Milton, the strongest storm forecast to strike Tampa Bay in more than a century, churned in the Gulf of Mexico, edging ever closer to its target.

Hundreds of thousands of Floridians, heeding urgent warnings from authorities to flee while they still had the opportunity, were caught up in the traffic jams as they headed inland to safety. Some even took to the air, with three people injured as their small plane crashed into Tampa Bay on Tuesday morning during their attempt to escape.

“There will likely not be enough time to wait to leave on Wednesday,” the National Hurricane Center in Miami cautioned in a mid-morning advisory.

Families who abandoned their homes in evacuation zones in low-lying coastal areas such as Clearwater and St Petersburg – where Milton’s storm surge could peak at anything up to 15ft (4.5 metres) – were uncertain what they would return to.

But the risk of staying put, as so many did to their cost during Hurricane Helene, which roared through Florida’s Panhandle and into the Carolinas and beyond only 11 days ago, was not an option.

Recalling the death toll from Helene, which is at least 227, the Tampa mayor, Jane Castor, was as blunt as she could be in urging people to leave. “I can say this without any dramatization whatsoever: if you choose to stay in one of those evacuation areas, you are going to die,” she said in an appearance on CNN.

Her words have resonance. Florida’s west coast has seen this before, most recently in 2022 when Hurricane Ian struck south of Tampa Bay at a cost of 149 lives. The majority drowned in an 18ft storm surge, which is essentially a rushing wall of ocean water that a hurricane’s winds pushes inland – and there were questions regarding why authorities delayed an evacuation order until the day before landfall.

For many, the call came too late, and people who were reluctant or lacking the resources to join long lines of traffic opted to shelter in place.

A growing number of gas stations were flashing “empty” signs as data from fuel markets tracker GasBuddy showed that by 6.30pm on Tuesday, 7,912 gasoline stations in Florida – about 17.4% of the total – had run out of fuel.

Kinder Morgan has shut its Central Florida Pipeline system, which moves refined products between Tampa and Orlando, the company said in an emailed statement. It has closed all fuel delivery terminals in Tampa, but expects trucks to be able to pick up fuel from Orlando wholesale racks until winds exceed 35 miles per hour.

Fuel trucks cannot safely deliver at wind speeds exceeding that threshold, wholesale distributor Mansfield explained, and said it expects wind conditions to bring all Florida fuel deliveries to a near-halt by Wednesday.

Refiner CITGO Petroleum and infrastructure and logistics provider Buckeye Partners are also shutting down their Tampa terminals, the companies told Reuters.

On Tuesday, hurricane refugees were filling hotel rooms in Orlando usually occupied by tourists and convention-goers, or heading north or south away from the danger zone, into areas of Georgia unaffected by Helene or to the Miami metropolitan area in south-eastern Florida.

“For every room we’ve had to cancel due to a convention or something not being able to get into the area, we’re refilling that room with somebody who’s impacted by this storm,” Jennifer Rice-Palmer, director of guest contact at Orlando’s Rosen Centre hotel, told the Orlando Sentinel.

The newspaper spoke to Nick Santos, an evacuee from Tampa who was taking advantage of the hotel’s discounted “distress rates” with his wife Tara and their children Scarlett, six, and Cole, three.

“It’s part of living where we live, but it could be a big, scary thing for them,” Santos said, explaining why he left early with his children and was taking them to a theme park. Disney said it was closing its theme parks on Wednesday afternoon until at least Friday.

Emergency shelters were also welcoming evacuees, with spaces still available in several Gulf coast counties on Tuesday.

Back in Tampa, meanwhile, rental companies ran out of vehicles, gas stations were emptied of fuel, and many supermarkets sold out of storm essentials including water, paper towels and cleaning supplies.

Florida’s governor, Ron DeSantis, lifted tolls on major highways and ordered breakdown lanes open to try to ease the flow. But officials said traffic levels were above 150% of normal, and accidents were blocking some routes.

“Unfortunately every storm we see traffic fatalities because people wait until the last minute to leave,” Florida’s transportation secretary, Jared Perdue, said at a Tuesday morning press conference.

A small plane carrying four people and a dog crashed into Tampa Bay on Tuesday morning shortly after takeoff from St Petersburg’s downtown Albert Whitted airport. The occupants were rescued by nearby boaters, and three were taken to hospital with non-life-threatening injuries, according to the Tampa Bay Times. The plane reportedly sank.

Analysts fear that the Tampa Bay area, home to more than 3 million people – many of whom have never experienced a hurricane of Milton’s magnitude – is particularly vulnerable.

“It’s a huge population. It’s very exposed, very inexperienced and that’s a losing proposition,” Kerry Emanuel, a meteorology professor at the Massachusetts Institute of Technology, told the Associated Press, referring to the storm as the “black swan” worst-case scenario experts have feared for years.

“I always thought Tampa would be the city to worry about the most.”

Since the Covid-19 pandemic, tens of thousands of Americans have moved to the area, with 51,622 new residents from 2022 to 2023, making it the country’s fifth fastest-growing metropolitan region, according to the US Census Bureau.

Meteorologists at AccuWeather reinforced the “get out early” message, warning that Milton could bring a “worst-case impact” for the Tampa Bay area even before Wednesday night’s expected landfall.

“You do not want to wait for storm surge to start occurring before you take action. We have seen so many preventable tragedies during Hurricane Helene and Hurricane Ian,” said Jon Porter, AccuWeather’s chief meteorologist.

“Please get out of areas at risk of this devastating storm surge while you still can. We are very concerned that Hurricane Milton could become one of the most damaging and [costly] storms that Florida has ever seen.”