For Florida, the state with the most golf courses in the United States, rising summer temperatures are forcing changes to the way the game is played.

Andy, a 43-year-old resident of Jacksonville who asked that his last name be withheld, follows a mental checklist to deal with oppressive summer conditions on the golf course.

“Drink water beforehand, bring electrolyte powder for drink mixes, wear a wide-brim hat, wear sunscreen and bring a cooling towel,” he told Yahoo News.

During July and August, the hottest months in the state, many golfers vie for early morning tee times to avoid being on the course when the heat and humidity conspire to make playing conditions miserable. That demand has also made morning tee times more expensive, so Andy opts for a late afternoon start time, hoping that the heat will diminish as evening falls.

“I try to play courses near waterways to increase the breeze,” he said. “If it gets over 100, I tend to avoid that.”

Tallahassee resident David Houck, 58, a rhetoric professor at Florida State University, said that in recent years he and a friend have opted for early evening tee time to try to squeeze in nine holes.

“We would come off the golf course as it was getting dark. We’d get to our cars and it was pitch-black,” he said, adding, “We’d oftentimes be soaking wet, depending on the heat and humidity.”

Temperatures in Florida have been steadily increasing since the dawn of the industrial revolution, Emily Powell, assistant state climatologist at the Florida Climate Center at Florida State University, told Yahoo News. But the rate of temperature rise has sped up in recent years.

“The past decade has been especially warm,” Powell said. “We’ve been warm throughout the 20th century but we’re pretty much 2-3 degrees Fahrenheit warmer over this last decade compared to prior years going back to 1895.”

But it’s not just the increase in temperatures that’s complicating a summer round of golf; studies have found that relative humidity levels are also rising in Florida. The combination of temperature and relative humidity is what determines the heat index, or what it feels like outside, and there too, Powell said, research shows “increasing trends in the average daily heat index from June through August.”

“Basically the heat wave season is expected to get longer,” Powell said, citing a 2023 study led by researchers at FSU that concluded that summertime heat waves could be extended by two months if humankind continues to burn fossil fuels at current levels.

While playing golf in extreme heat is less dangerous than, say, sports like football, it does pose health risks.

“Every year we have someone that doesn’t hydrate enough, or decides to have a few adult beverages and isn’t properly hydrated, and heatstroke can certainly kick in,” Kevin Swan, director of golf at Mediterra, a private club with 500 golf members in Naples, told Yahoo News. “Last summer we did have a guest who was visiting who did not drink much water and didn’t eat a lot and developed heatstroke when he was out playing. Paramedics arrived. We had to get him IVs. It’s definitely something that we’re always concerned about.”

Florida has the highest number of heat-related illnesses of any U.S. state, according to the Florida Policy Institute, and the number of heat-related deaths has risen sharply in recent years.

In hot weather, the human body sweats to cool itself off. But when the humidity in the air gets too high, that sweat can’t evaporate, dramatically raising the risk of heatstroke.

“When I first got here, especially going into the summer months, it was, ‘Hey, make sure you hydrate,’ but there wasn’t anything done on a daily basis,” Swan, who has been with Mediterra for seven years, said. “Now when members and guests go out during the summer it’s a constant reminder: Make sure you’re hydrating, make sure you’re drinking before you get to the golf course, tips and data on those things.”

Florida golf clubs like Mediterra now routinely include information on websites and in clubhouses warning of the dangers of heatstroke.

“Do not wait until you are thirsty as that is a sign of dehydration,” the Blue Sky Golf Club advises players on its website. “Make sure you drink after every time you swing your club when you golf in Jacksonville, FL.”

As global temperatures have risen due to climate change, Florida courses have had to adapt in a variety of ways. Like many clubs, Mediterra replaced fairway grass with Platinum Paspalum, a more heat-tolerant Bermuda variety, and installed additional drainage in low-lying areas to handle extreme precipitation events.

“We are so close to the water table so when there is a lot of rain over a period of time and there’s nowhere for the water to run off, you’re going to struggle with wet conditions,” Swan said.

For courses located directly along Florida’s 1,350 miles of coastline, sea level rise has forced more drastic measures.

Plagued by frequent flooding, the Seminole Golf Club, a private club located just north of Palm Beach, has embarked on an ambitious and expensive renovation project, installing French drains under fairways and greens and pumps to try to push water out, and raising portions of its seaside course by as much as 2 feet.

“People throughout the game are concerned about this issue,” Nelson Caron, Seminole’s director of golf course operations, told Global Golf Post. “And I have been getting countless calls from clubs going through the same thing since we presented our plan to membership last year.”

Sea levels across Florida have risen by as much as 8 inches since 1950, according to the Florida Climate Center, and, as with temperature increases, that rate is accelerating, rising by 1 inch every three years over the past 10 years.

While Seminole says it will reevaluate its plan for saving its golf course, approximately half of its acreage is either at sea level or just 1 or 2 feet above that. That doesn’t bode well for its long-term future. Sea levels are projected to rise between a foot and a foot and a half over the next 15 years, Powell said, “but if you go a little bit further out, to 2080, that’s probably going to be around 3 feet or more.”

For now, golf remains a beloved pastime in Florida and a major economic driver, with course and country club revenues in the state hitting a record $3.5 billion in 2024, according to Statista.

But even those with a vested interest in keeping people on courses throughout the summer months acknowledge that things have changed.

“No matter how hot it gets, the love for golf will always draw you towards our challenging, yet rewarding course, but you have to make sure you can stay cool under the pressure,” the Founders Club, a private golf club in Sarasota, says on its website.

For Vic Garrison, a former club pro at Indian Hills Golf Course in Fort Pierce, the new reality means certain areas are off-limits in summer.

“Stay the hell out of the center of the state — no breeze and more humidity,” he said.

For others, like Andy of Jacksonville, summer golf in Florida may soon be a thing of the past.

“If summer temps continue to rise,” he said, “I may have to take off the summer months, like Northerners take off the winter months.”