MELBOURNE, Australia (AP) — Melbourne is known for its wacky weather. The joke here is that you can experience four seasons in one day. But the heat wave that started Tuesday and is forecast to end on the weekend has brought what meteorologists are estimating as the longest stretch of weather this hot since 1908.
That's been bad news for the tennis players at the Australian Open, where Thursday was the hottest day so far.
There were the unlucky morning starters, like Maria Sharapova who played in 43 degree C (109 F) heat and cooled off at changeovers with ice vests on their bodies and ice collars around their necks. Some called trainers to complain of head spins, blurred vision and cramping from dehydration.
By mid-afternoon, the Australian Open invoked its "Extreme Heat Policy" and suspended play for four hours on outdoor courts and closed the retractable roofs at Rod Laver and Hisense Arena. That allowed other stars like No. 1 Rafael Nadal, No. 6 Roger Federer and No. 2 Victoria Azarenka to play indoors.
"I never actually experienced the heat today," said Federer, who advanced easily to the third round.
Later in the day after temperatures dipped, Sloane Stephens looked up to see "crazy, ridiculous" lightening zig-zagging through the sky, which caused another delay.
Here are five things to know about how the heat effects the Australian Open:
GUIDELINES FOR HALTING PLAY: Matches can be stopped and the tournament's two retractable roofs closed at the discretion of tournament director Wayne McKewen. He makes his decision while monitoring the wet bulb globe temperature index, a calibration based on temperature, humidity, wind speed and sunshine. Extreme heat halted play during several days of the 2006 tournament. The hottest Australian Open on record was in 2009, when the average temperature across two weeks was 34.7 degrees C (94.46 F).
THE CONTROVERSY: The heat and the tournament's delayed decision to halt play sparked debate about whether it was dangerous to have allowed matches since Tuesday when the heat wave started.