The 2026 Fifa World Cup has barely passed its first week, but one opponent is already making its presence felt across all 48 squads: the American summer.
Declan Rice was admonished by his mother for turning up to the England team photoshoot sunburnt. Barcelona’s Pedri and Gavi trained in ice vests. Germany coach Julian Nagelsmann has banned his players from retreating into air-conditioned spaces, convinced that acclimatisation is the only real solution. These are not sideshows. They are the daily calculus of a tournament being played in conditions that no amount of tactical preparation can fully neutralise.
Fifa has responded by institutionalising three-minute hydration breaks at the midpoint of each half — time for players to rehydrate, lower core body temperatures, and receive tactical instructions.
England’s German coach Thomas Tuchel has been candid about his unease.
“We are not used to being in this kind of heat and humidity. There will be a lot of challenges in this World Cup. The heat is one of them but we are prepared already,” he said earlier this month.
His anxiety is compounded by a more familiar concern: most of his players arrive off the back of a gruelling club season, and fatigue tends to announce itself in the later rounds.
The worry is not new, but the scale is. This is the first 48-team World Cup, the first to be spread across three countries and 16 venues, only four of which — in Dallas, Atlanta, Houston, and Vancouver — have retractable roofs. Those four stadiums will host 31 of the tournament’s 104 matches. The remaining 73 will be played under open skies, at the mercy of whatever the North American summer decides to deliver.
The numbers behind that exposure are sobering. At the centre of Fifa’s heat-safety protocol is the Wet Bulb Globe Temperature, or WBGT — a composite index to measure how effectively the human body can cool itself. It factors in not just air temperature but humidity, wind speed, and radiant heat from the sun: the full burden the body must manage. A WBGT of 26 degrees Celsius is the point at which FIFPRO, the global players’ union, recommends mandatory cooling breaks. At 28 degrees, it recommends postponing play altogether. Fifa’s own threshold for considering postponement sits considerably higher, at 32 degrees Celsius.
According to an analysis by World Weather Attribution, a climate modelling organisation, roughly a quarter of this tournament’s 104 matches are being played in cities where conditions are likely to exceed that 26-degree WBGT threshold. Five matches are expected to breach the 28-degree mark. Miami, Kansas City and East Rutherford in New Jersey — where the final is scheduled for July 19 — are among the highest-risk venues. The warning signs were visible last summer at Fifa’s Club World Cup, also held in the United States, where heat and storms interrupted six matches and Chelsea midfielder Enzo Fernandez said he had to lie down on the pitch after feeling dizzy in 36 degree Celsius heat.
Copa America 2024, played in Kansas City, offered an even starker preview: temperatures hit 34 degrees Celsius, and with humidity factored in, the real-feel was closer to 40 degrees. An assistant referee fainted on the pitch.
Ecuador players during a hydration break in Philadelphia on Sunday. Reuters
History offers a useful frame.
The 1986 World Cup in Mexico remains the most notorious case of institutional indifference to player welfare: no hydration breaks, no cooling technology, stadiums without roofs, and kick-offs scheduled at noon to suit European television markets. Eventual winning captain, Argentina’s Diego Maradona, not a man given to diplomatic restraint, was furious. Eight years later, when the United States last hosted the World Cup, a historic heatwave made conditions almost as severe; teams adapted as best they could, with none of the structural support now available.
The contrast with Qatar 2022 ran in the opposite direction — the entire tournament was moved to November-December to avoid desert heat, and the air-conditioning inside some stadiums was reportedly so powerful that spectators found themselves reaching for jackets by the second half.
The teams at this World Cup have arrived better prepared than any generation before them. Sports science has made heat management as routine a part of tournament planning as set-piece rehearsal. So far, it shows: no squad has visibly adjusted its starting line-up or style of play to account for the conditions. Croatia’s Zlatko Dalic is not leaving Luka Modric, 40 years old, on the bench out of concern that he might wilt. Brazil boss Carlo Ancelotti, looking characteristically unruffled in his suit on the touchline in New Jersey on Saturday, substituted Casemiro in the 34th minute not because the humidity had beaten him, but because Morocco’s 19-year-old Ayyoub Bouaddi was dismantling him.
The fans in the stands have been less well looked after. Fifa initially barred spectators from bringing refillable water bottles into venues on security grounds — a decision that drew swift and widespread criticism. The rule was quietly reversed, with sealed disposable bottles now permitted. It was a small concession, and probably a necessary one. The players on the pitch have cooling vests and hydration schedules and teams of sports scientists watching over them. The supporters who paid to watch them have the sun, and whatever they can carry through the turnstiles.
The conversation about heat will not end here. The 2030 World Cup — split across Spain, Portugal and Morocco — will revive it all over again, in a different climate with a different set of trade-offs. Each edition finds new ways to cope. This one is no different. It is just more visible.