3.5 degrees Fahrenheit.
That’s how much hotter Florida has become, on average, since 1950, according to the Florida Climate Center.
The number may seem small, but it has big consequences. It means Florida is warming faster than the rest of the world: the global trend is an average 2.7 degrees F since 1950.
And it means Florida is no longer merely hot, but hazardous.
“We are the southernmost state, so with our latitude, we have long summers and extended periods of warmth,” said state climatologist David Zierden at the Florida Climate Center in Tallahassee. But since the early 2000s, particularly in the past decade and a half, the state has seen "nothing but above-normal temperatures year after year," he said.
Last year, 2024, was the warmest nationally and worldwide since record-keeping began. It was the 5th-warmest year on record in Florida since the state’s weather records began in 1895, and the hottest summer.
July was the hottest ever on record for Orlando, Punta Gorda, Tampa Bay and Fort Lauderdale. “If you define summer as June, July and August, as meteorologists do, we experienced our hottest summer on record (in 2024),” said Zierden.
It’s not just on land. Ocean temperatures, too, have climbed to unprecedented highs. That includes the Gulf of Mexico, where warm waters fuel hurricanes. The Gulf saw record peaks in summer and fall 2024, according to the University of Miami’s Upper Ocean Dynamics Lab.
Zierden and other scientists who research the climate said that the upward temperature trajectory shows no signs of slowing.
Increases in heat-trapping emissions, such as burning fossil fuels, are to blame. Even running the air conditioners that help people deal with the heat causes additional emissions.
Meanwhile Florida’s geography helps amplify the effects of rising temperatures. Positioned near the equator with its flat terrain and surrounded by warm seas, the state experiences intense sunlight and high humidity, trapping heat and creating a suffocating atmosphere.
At the same time, the state’s intense population growth and development have intensified the so-called urban heat island effect. This occurs when cities replace natural vegetation and waters with dense concentration of pavement, buildings, concrete and other surfaces that absorb and maintain heat, making it significantly warmer.
So how hot is Florida going to get? The state, along with the rest of the world, has crossed a threshold.
“I think Florida is going to become increasingly more and more uncomfortable,” said Stephen Mulkey, an environmental scientist and professor at the University of Florida who teaches several climate-related courses.
Mulkey said even if the world could reduce global emissions to close to zero, it would merely halt warming, not revert to what temperatures once were.
“If we were to rapidly approach and lower global emissions, rapidly approach net zero, we could stabilize the climate, but no, in the next several generations, there's no returning to preindustrial [climate],” Zierden agreed.
Still, just how hot it’s expected to get in the next 10, 20 or 50 years is hard to pinpoint, depending on a variety of factors and actions, such as how much humans can curb emissions.
Even in low-emissions scenarios, extreme heat days, defined as days at or above 95°F, are projected to increase in the state, according to the Florida Climate Center.
Such temperatures pose real risks to human health. Florida has the highest numbers of heat-related illness in the United States, according to a 2024 report by the Florida Policy Institute, with the most recent data showing 31,011 emergency room visits and hospitalizations between 2018 and 2022.
“It's very much the case that projected temperatures for heat index and for wet-bulb temperature through much of the more subtropical to tropical zones of Florida will achieve limits of survivability outside sometime before 2050,” said Mulkey.
Wet-bulb temperature is a way of measuring heat stress out in the sun, taking into account humidity, sun angle, cloud cover and other factors that impact work and exercise outdoors. Scientists have long thought the survivable wet-bulb temperature was about 95 F for six hours of unshaded outdoor exposure. But new research shows it may be lower, especially for older and other vulnerable people.
Zierden argues that extra care needs to be taken for the agricultural, construction workers, athletes and others whose work requires exertion outside.
That care has not happened so far. Miami-Dade was the only county in Florida that had passed protocols outlining when outdoor workers need shade, rest and water. But in the 2024 session, the Florida Legislature banned cities and counties from requiring employers to give such protections.
Despite the state’s pre-emption of local ordinances, cities and counties are taking the lead on a number of cooling strategies. Those include mitigating the heat-island effect by increasing tree cover; opening community cooling centers during extreme heat and in power outages such as those that follow hurricanes; and increasing access to pools and other cooling waters during the hottest times of the year.
“We need to adapt,” Zierden said. “We need to take measures to protect our population, our society, our infrastructure, from these kinds of changes.”
