The first Grand Slam of the season is played right in the heart of the Australian summer, and that often means brutal heat. In 2014, it reached a staggering 43.9°C (111°F), and nine players were forced to retire from their opening matches because of extreme conditions. That alarming tournament became a turning point, and it’s exactly why the Australian Open stepped in a few years later, introducing the Heat Stress Scale in 2019 to protect players.

When the heat climbs too high, it’s no longer just uncomfortable; it can be dangerous. That’s when officials have the power to suspend play, ensuring players aren’t pushed past safe physical limits under the scorching Melbourne sun.

Those decisions fall under what’s known as the Extreme Heat Policy, a set of guidelines used to judge whether conditions are safe and whether matches should continue. We saw it in action at the 2023 Australian Open, when temperatures hit 36°C, and the stress scale reached level five, forcing play on outside courts to be suspended. Now, let’s take a closer look at the Australian Open 2026 Extreme Heat Policy and everything tennis fans should know about how the tournament handles the heat.

What is the Australian Open 2026 Extreme Heat Policy, and how does it work?

The official Australian Open website clearly lays out how the Heat Stress Scale works and how it’s applied when conditions become extreme during the tournament. Alongside that, the ATP Board has approved a brand-new heat rule that will take effect from the 2026 season, bringing the men’s tour in line with the WTA and further strengthening protections for players competing in brutal conditions.

The new regulation is based on the Wet Bulb Globe Temperature (WBGT) and introduces clear, defined thresholds for cooling measures and for suspending play in best-of-three singles matches.

One of the key provisions is the introduction of a 10-minute cooling break.

Cooling measures will be triggered when the WBGT reaches 30.1°C or higher during the first two sets of a best-of-three singles match. Once activated, either player can request a 10-minute cooling break after the second set, and it applies to both players.

During that break, players are allowed to fully focus on recovery.

They can use cooling methods, hydrate, change clothing, shower, and even receive coaching, all under the supervision of ATP medical staff. It’s a window designed specifically to help players lower their body temperature and reset before heading back into demanding conditions.

Another major provision covers suspension of play.

If the WBGT goes beyond 32.2°C, play will be stopped altogether. At the heart of this new heat rule is player health and safety, introducing a structured, medically supported way to manage extreme temperatures to protect players while also improving conditions for spectators, officials, ball persons, and tournament staff.

At what level is play suspended under the heat policy?

Under the Australian Open’s Heat Stress Scale, conditions are continually monitored using four climate factors: radiant heat (strength of the sun), air temperature in the shade, relative humidity, and wind speed, measured around the Melbourne Park precinct. The scale runs from 1 (temperate playing conditions) up to 5, and when it reaches level 5, play is suspended.

When the Heat Stress Scale reaches 5.0, the Tournament Referee will suspend the start of matches on outside courts. Matches already underway don’t stop immediately. Instead, they’re allowed to continue until they reach a natural break, which means either the end of an even number of games in the current set or the completion of a tie-break, before suspending play.

And if you’re curious to know about how matches on show courts are handled, on the major show courts with roofs: Rod Laver Arena, Margaret Court Arena, and Melbourne Arena, play also stops after an even number of games in the set or the completion of the tie-break once level 5 is reached. At that point, the Tournament Referee may decide to close the roof for the remainder of that match and subsequent matches while the Extreme Heat Policy remains in effect.

In short, level 5 on the Heat Stress Scale triggers suspension of play, and matches already in progress are finished to the next even-game break or tie-break before they stop.

Who decides when play is suspended, and how is it measured?

The tournament referee is the official with the authority and responsibility to interpret those Heat Stress Scale readings and determine whether extended breaks, suspensions of play, or resumptions are necessary. This means the referee doesn’t just look at air temperature alone.

They consult the full Heat Stress Scale data and assess the real-time conditions across the precinct before deciding whether the policy should be invoked. When level 5 of the scale is reached, signaling extreme heat stress, the referee can suspend matches on outside courts and pause matches in progress at natural break points before stopping play altogether.