The furnace is set to ignite at Wimbledon, as this year's Championships gear up for a potentially sweltering fortnight. Temperatures soared last year to a record-breaking 33C on opening day, and forecasts suggest similar conditions could return to SW19 throughout the tournament.
Enter the All England Club's heat rule, designed to safeguard player welfare. If the heat stress index – aka the Wet Bulb Globe Temperature (WGBT) – reaches or surpasses 30.1C, players can request a 10-minute break. This comprehensive measure takes into account air temperature, humidity, and surface temperature to give us a 'feels-like' reading. The WGBT is measured 30 minutes before play commences, and again at 2pm and 5pm daily. If triggered, the break would come between the second and third sets for women's singles matches and between the third and fourth sets for men's.
Defending champion Jannik Sinner has already given a glimpse into the heat rule's importance. His struggles in hot weather have been well-documented – he was knocked out of the French Open earlier this season during a scorching second-round match, although he attributed his performance to illness rather than the heat itself.
Wimbledon's approach to heat management is firmly in line with other major tennis tournaments. The Australian Open employs its own heat stress scale, enforcing a 10-minute cooling break at level 4.0 and suspending play entirely at its highest level of 5.0. Similarly, the French Open activates a 10-minute cooling break when the WGBT hits 30.1C, with a full suspension if it climbs to 32C.
But Wimbledon's heat management doesn't stop at player welfare – the club has also taken steps to safeguard spectators. The grounds now boast more shaded areas and additional water points, while fans are advised to stay hydrated, wear light clothing and hats, and take breaks from direct sunlight. It's a challenge that extends beyond the players, as rising temperatures pose a broader threat to major sporting events.