EVIAN RESORT GOLF CLUB, France — Lottie Woad battled not just the undulating slopes of the picturesque Amundi Evian Championship course to take an outright lead, but the weather too.

Temperatures soared to 90 degrees Fahrenheit on Friday as Woad, the fourth-best player in the world, hit eight birdies to go 11-under-par and one shot clear of Aki Awai. Woad, who is from Farnham, England, had to top up her Leeds United-embellished water bottle at almost every hole.

And while the 22-year-old might have the lead to herself for the first time at a major tournament, one thing she was not alone in on Friday was her constant use of a sun-blocking umbrella and plenty of SPF.

“You just don’t really get much breeze,” Woad said. “That’s the thing that makes it hot. The fairways are OK. Just the tee boxes are quite stuffy.”

Iwai let a 5-shot lead slip with an unhelpful double bogey on No. 6, her 15th hole of the day after starting on the back nine. The 24-year-old stayed under an umbrella throughout her round, stepping out only for tee shots.

Jacques Bungert, vice president of the tournament, says the refillable stations on tee boxes have already been used five times more than they were at the same stage last year. In between players teeing off, constant golf buggies are whizzing up and down the hills delivering giant Evian bottles to each hole.

Water from Evian’s famous bottling plant is put through a filtration system and used at the golf resort. To replenish the greens, head greenkeeper Adrien Petrocelli and his 60-strong staff were here in the early hours of the morning watering the short grass just as golfers with early tee-off times were arriving.

Jeeno Thitikul, who is in fifth place at 6-under-par, described the greens as “weird” and “bumpy” after her second round. Thitikul, the second-best player in the world behind only Nelly Korda (who missed the cut), was at the course just before 6am and watched ground staff watering the grass, which surprised her given it was so close to players taking to the course.

“I think they’re just afraid to get too dry and then we won’t be able to play,” Thitikul said. “Obviously, (it’s) not the best that we can see from Evian Resort, but I know the weather kind of changes a little bit.”

Greenskeepers have had their work cut out for them this week to keep playing conditions as close as they can to major championship quality. (Stuart Franklin / Getty Images)

Mao Saigo is tied for third and said: “Every year it gets hotter and hotter here.”

That is perhaps why broadcast cameras zoomed in when they spotted Charley Hull holding an ice cream on Thursday. Hull later confirmed the ice cream was for her caddie, but to deal with the heat she eats something on every other hole even if it is just a bite. Protein bars, special juices and bananas have fuelled Hull’s first two rounds at Evian, where she is 5 shots back of her fellow Englishwoman, Woad.

“I just drink loads of water on every hole and have loads of electrolytes. I think the key is to eat,” Hull said Thursday. On Friday, after hitting 17 greens in regulation, she felt the course was a tad wet.

“Some of the holes where they bounce on, it was stopping within an inch with a 6-iron,” Hull said. “I think they just overwatered them a little bit.”

Petrocelli and his team, which is usually made up of 26 people, have their work cut out amid a relentless French heatwave. And even though Évian-les-Bains is cooking, the heat here has not been as bad as other parts of the country where red weather warnings remain in place. Some put that down to the proximity of Lake Geneva, which Thitikul says you can jump into if you have a bad day on the course.

Most of the players had their arms completely covered by long, white sleeves. Frenchwoman Perrine Delacour, who is pleased to have made the cut in her home major, was among them and said it was her dermatologist who instructed her to wear a sweat-wicking underlayer when the heat is as inescapable as it was Friday.

Spectators seek shade during the first round of the Evian. (Marco Goncalves / Hans Lucas / AFP via Getty Images)

Players are familiar with such testing climates; therefore, they are well prepared. And some don’t mind it. Hinako Shibuno said the weather here is better than in her native Japan, where the humidity can be stifling. Ruoning Yin is based in Texas and wasn’t worried about the weather because, “Dallas is way hotter”.

“We went to Mexico last year and that was probably the hottest the LPGA Tour has been,” Joakim Hilton, Jiwon Jeon’s caddie, said. “Now everyone has that as a reference point; that’s the max. It was above 40 Celsius, and the humidity it was close to 95 every day. We had a few caddies and players fainting during the tournament week.”

Caddies play a key role in helping players navigate the course and the conditions, but they also have to ensure they manage their own well-being.

“You try to make sure to hydrate, eat and sleep well. I mean it’s all one package,” Hilton, who is based in San Diego, said. “Weather is a big part of a caddie’s preparation. We always look ahead at how the week is gonna be. At the winds and temperature. That is part of the routine and we adjust accordingly.”

Those who made the cut may rejoice at the forecast for Saturday, which predicts clouds. While that may lessen the need for umbrellas, the heat is not going away and will remain one of the biggest challenges when getting around this slope-heavy course on the north side of the Alps.