What Is Australian Open Extreme Heat Protocol? All You Need To Know

The Australian Open Extreme Heat Protocol (AO-EHP) was triggered for the second time this tournament on Tuesday as Melbourne endured record-breaking temperatures.

Australian Open 2026 organisers reimposed heat relief measures after conditions worsened late on Day 10, with forecasts that temperatures could reach 45°C.

How Australian Open Heat Stress Scale Works

The Australian Open uses a Heat Stress Scale, introduced in 2019. The scale runs from Level 1 to Level 5, and factors in air temperature, radiant heat, humidity, and wind speed. The system was designed to ensure consistency across courts while minimising heat-related illness.

Once the index reaches Level 5, play is automatically suspended on outside courts for both men’s and women’s singles, and the retractable roofs are closed on the three main arenas at Melbourne Park. This happened during Jannik Sinner’s match against Eliot Spizzirri on centre court on Saturday.

Roof Closed After Sabalenka vs Jovic

Although the roof was open at the start of Day 10, conditions deteriorated rapidly. After Aryna Sabalenka defeated Iva Jovic 6-3, 6-0, tournament officials closed the roof ahead of the men’s quarter-final between third seed Alexander Zverev and American Learner Tien.

“At the end of the match, it was really hot out there,” Sabalenka said. “I’m glad they kind of closed the roof kind of, like, almost halfway, so we had a lot of shade in the back, so we could go back and stay in the shade.

“I guess, yeah, as a woman, we are stronger than the guys,” she added, laughing. “So they had to close the roof for the guys so they don’t suffer!”

Sabalenka said she knew before stepping on the court that precautionary measures would be triggered as the heat index climbed.

“I knew … they won’t let us play (in) crazy heat,” she said. “If it would reach 5, they would definitely close the roof, so I knew that they were protecting us, our health.” Yeah, anyway, when we’re finished… it was 4.4, so it was quite hot.”

Who Decides When Play Is Suspended

The tournament referee holds final authority over suspending play or delaying upcoming matches. If outside courts are suspended, the referee may also decide whether arena roofs should be closed or remain shut for subsequent matches.

Once the referee determines that play can resume, players must be given a minimum of 30 minutes’ notice before matches restart.

Cooling Breaks Explained

When the Heat Stress Scale reaches Level 4, organisers can introduce an extra 10-minute break. This takes place between the second and third sets in women’s singles and between the third and fourth sets in men’s singles.

However, if an arena roof is closed before the end of the first set in a women’s match or before the end of the second set in a men’s match, no extra cooling breaks are added.

(With AP Inputs)