Professional tennis is a highly tuned, multi-million dollar industry in which the weather is a major consideration.
With the Australian Open underway, adapting to the weather will be critical for success at Melbourne Park over the next fortnight.
It is not just the players' comfort that is affected by the weather — it also changes the performance of the balls and the way racquets are strung.
Veteran racquet stringer Steve Harris, who is working on his 11th Australian Open for big names such as Rafael Nadal, said weather was critical.
He and the 20 or so other stringers from around the world fine-tune up to 500 racquets a day to make sure they are perfect for each player and the conditions they will face.
Mr Harris said temperature, wind, rain and moisture all impacted player demands during a major tournament.
So how does it work?
As demonstrated in countless science fair experiments over the years, as temperature goes up the air pressure inside a ball increases, causing it to bounce more.
It may only be a tiny difference, but it all matters when you are aiming for the lines.
"If the temperature tends to rise, the ball tends to skid on a bit more, brush across the surface and come through a bit quicker," Mr Harris said.
"As the court gets cooler the ball tends to grab the surface a little bit more. It doesn't come through as quickly, so any spin for example is feeling slightly exaggerated and has more of an effect.
"The other factor they have to take into account is the humidity. Moisture in the air as humidity rises makes the ball heavier, slower through the air, and the felt fluffs up a little bit more."
Other factors such as wind and sun are common enemies of the pro and amateur alike.
"Most tennis players don't like wind because it takes away the ability for them to be pinpoint with their shot production," Mr Harris said.
Who benefits in different conditions?
According to Mr Harris, hot, dry and therefore fast conditions will benefit attacking players such as Nick Kyrgios and Roger Federer, while defensive players like Nadal benefit from cooler, slower conditions.
"If the court becomes a bit quicker and is designed that way to keep the speed relatively high through the surface, then that suits someone like Roger Federer who wants to play attacking shots … they don't want to get bogged down in long rallies," he said.
Players use their racquet strings to try to compensate for the conditions, which is where Mr Harris and his finely tuned colleagues come in.
"If you think about it as a trampoline, it's a trampoline which becomes more bouncy or less bouncy," he said.
"So [as] you are changing the tension, you are putting on the trampoline's springs to get more or less bouncy yourself.
"[Players] might go up in [string] tension to try and compensate for tension loss due to the heat, so they start out a bit higher … in order to keep the spin up and the power level down, to compensate for the extra bounce of the ball."
When it gets cooler the opposite is true.
"Players will generally go down in tension to get a little more elasticity, so it will catapult the ball more and they can get easier power without over straining."
Melbourne is known for its ability to produce four seasons in a day, which can be a real challenge for long matches.
"Rafa goes on court with six racquets per match all specially strung. He will use those, but he will have a number of racquets in his bag," Mr Harris said.
"As the game progresses, maybe gets to three of four hours into the match or conditions change, he might send me some more racquets in to string while he is in his match, that I will send back to make sure he has a fresh re-string, a more controllable re-string.
"Five hours is a long time in a men's tennis match and Melbourne can throw up a lot of different conditions; they have to adapt as they go as best they can."
Extreme heat policy courts controversy
One man who knows all about changing conditions at the Australian Open is Bob Leighton, official forecaster at the Australian Open for the 11th year.
It is his job to advise the tournament referee on the weather over the fortnight.
At the Australian Open, rain, lightning and extreme heat can cause play to stop on the outdoor courts.
The extreme heat policy has caused a bit of controversy over the years.
In 2009 the tournament suffered through three days of over 40 degree temperatures and play was called off, while in 2014 Canadian player Frank Dancevic reportedly called the conditions inhumane before play was eventually stopped.
Ultimately, when to employ the extreme heat policy is up to the discretion of the tournament referee, but it is guided by a calculation called the wet bulb global temperature.
It is not to be confused with the wet bulb temperature (it's complicated, but basically it takes into account temperature and humidity).
According to Mr Leighton, most of the time the players themselves do not really want to stop.
"It is not only the players that are affected by these extreme weather events — it is the patrons, the ball kids and the security staff, all the staff who are associated with the event," he said.
How is it looking for 2018?
Mr Leighton expects a good day for tennis today with 31 degrees and sunshine, but it will heat up over the next few days.
"Thursday we expect some very hot weather, about 40 degrees here at the park," he said.
"That's about 1 degree hotter than the Melbourne forecast because at the park here there are a lot of buildings, a lot of concrete, a lot of asphalt and a lot of alleyways that tend to get hot."
He predicts Friday will stay hot courtside, with temperatures reaching up to 41 degrees before a change at around four or five in the afternoon, when the temperature should drop to about 26 degrees.ABC