Experts warn that cooling breaks and later kickoff times may be needed to cope with scorching temperatures when North America hosts the tournament
Leander Schaerlaeckens
Leander Schaerlaeckens
Fri 7 Mar 2025 11.00 GMT
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Throughout a playing career that wound through Spain, Mexico, and the sunbaked fields of Major League Soccer’s summers, American midfielder Tab Ramos was never hotter than at the 1994 World Cup in the United States.
The day before the United States men’s national team opened its tournament against Switzerland in the Pontiac Silverdome, it had been 99F (37C) in Michigan. By the 11.30 am kickoff on matchday, the temperature reached 90F (32C) again. Worse still, the Silverdome was an NFL stadium designed for winter – to keep heat in, rather than out. The first World Cup match played indoors was conducted in a dome without air conditioning. On the field, the temperature reached 106F (41C). The grass laid over the artificial turf had been watered so eagerly that, with the sun beating down on the stadium’s fabric roof, the air turned soupy with humidity.
“We were boiling in there,” Ramos says. “They were carrying people out from the upper deck; fans were passing out.”
The heat was one of the players’ biggest gripes all the way through to the final between Brazil and Italy in Pasadena, California, which kicked off in 100F (38C) temperatures. Fifa was unsympathetic. “Journalists predicted players would die [in Mexico],” a spokesman told the LA Times, pointing to the lack of casualties from the 1986 edition, where it was also hot and the air thin and smoggy, as some kind of perverse validation. “We encourage them to drink water.”
More than three decades on, with the World Cup returning to the United States along with co-hosts Mexico and Canada, the story may be much the same.
Fourteen of the 16 host cities for next summer’s biggest-ever, 48-team, 104-match World Cup are predicted to see afternoon temperatures high enough to endanger the players. So says a study of the 20-year meteorological record published in The International Journal of Biometeorology in January, which urges organizers to avoid afternoon kickoffs. Nine of the venues will probably experience a wet bulb globe temperature – a measure that combines the effects of the air temperature, humidity, solar radiation, and wind speed – above the safety threshold of 82.4F (28C) on more than half the afternoons of hot summers. The risks will be highest in half a dozen cities with open-air stadiums: East Rutherford, Foxboro, Kansas City, Miami, Monterrey, and Philadelphia. (An earlier study, published in October, made a similar prediction, forecasting “very high risk of experiencing severe heat stress conditions” in 10 of 16 venues.)
“The threat of extreme heat will be bigger at this World Cup than it was [at the 2022 World Cup in Qatar],” says Dr Donal Mullan, a climate scientist at Queen’s University Belfast and the lead author of the most recent study. “Some of these venues are kind of a disaster waiting to happen.”
The 2022 World Cup in Qatar was moved from the scorching summer months to November and December to protect the players. The highest wet bulb temperature – which is slightly different from wet bulb globe temperature – recorded during the World Cup in Qatar was 73.4F (23C) – a little less than 10 degrees below predicted figures in the US.
Fifa and US Soccer recommend that games implement cooling and hydration breaks when the WBGT exceeds 89.6F (32C). More cautious governing bodies, like the Australian federation, set a WBGT limit of 82.4F (28C) before matches can be delayed or even postponed. However, temperatures below those guidelines can still be dangerous. During the 2024 Copa América, held in the United States, an assistant referee collapsed from heat stress during a match in Kansas City when the WBGT was a mere 81.5F (27.5C). A few days earlier, defender Ronald Araujo had to be substituted out of Uruguay’s opening when WBGT reached the mid-80s, and the body’s physiological frailties were exposed. “The weakest link in the chain is going to break first and the heat will bring that about quickly,” says Dr Robert Huggins, a kinesiology professor at the University of Connecticut who worked with the US women’s national team and the Portuguese men’s team to prepare them to play in major tournaments in high heat. “From a thermoregulation perspective, the hotter the ambient temperature and the higher the humidity, the worse our body can dissipate the heat. If my sweat cannot evaporate off the surface of my skin and be accepted by the environment, I will not be able to physically cool my body.” game with Panama in Miami due to dehydration.
Kickoff times have not been announced for the 2026 World Cup yet, and Fifa did not respond to an email asking whether it would consider player safety in scheduling games and avoid afternoon kickoffs at its hottest venues.
“That’s the obvious answer, schedule it outside of these [afternoon] kickoff times,” says Mullan. “If you avoid those afternoon hours between 12 and 6 pm, that would make an enormous difference.”
The tournament’s expanded format will make that difficult. For most of the first two rounds of the group stage, there will be four matches a day. During the last round of group-stage matches, there will be six games a day. The round of 32 has five days with three scheduled matches. To maximize TV viewership around the world, a good number of those matches will probably have to be played in the afternoon heat.
The study Mullan authored was based on the summer temperatures from 2003 through 2022, which is to say, Mullan points out, that it represents a conservative estimate that did not incorporate the record heat in the summers of 2023 and 2024. Nor, for that matter, does it account for the possibility of wildfire smoke.
Experts warn that cooling breaks and later kickoff times may be needed to cope with scorching temperatures when North America hosts the tournament.
Leander Schaerlaeckens
Leander Schaerlaeckens
Fri 7 Mar 2025 11.00 GMT
Share
Over the course of a playing career that wound through Spain, Mexico, and the sunbaked fields of Major League Soccer’s summers, American midfielder Tab Ramos was never hotter than at the 1994 World Cup in the United States.
The day before the United States men’s national team opened its tournament against Switzerland in the Pontiac Silverdome, it had been 99F (37C) in Michigan. By the 11.30 am kickoff on matchday, the temperature reached 90F (32C) again. Worse still, the Silverdome was an NFL stadium designed for winter – to keep heat in, rather than out. The first World Cup match played indoors was conducted in a dome without air conditioning. On the field, the temperature reached 106F (41C). The grass laid over the artificial turf had been watered so eagerly that, with the sun beating down on the stadium’s fabric roof, the air turned soupy with humidity.
“We were boiling in there,” Ramos says. “They were carrying people out from the upper deck; fans were passing out.”
The heat was one of the players’ biggest gripes all the way through to the final between Brazil and Italy in Pasadena, California, which kicked off in 100F (38C) temperatures. Fifa was unsympathetic. “Journalists predicted players would die [in Mexico],” a spokesman told the LA Times, pointing to the lack of casualties from the 1986 edition, where it was also hot and the air thin and smoggy, as some kind of perverse validation. “We encourage them to drink water.”
More than three decades on, with the World Cup returning to the United States along with co-hosts Mexico and Canada, the story may be much the same.
Fourteen of the 16 host cities for next summer’s biggest-ever, 48-team, 104-match World Cup are predicted to see afternoon temperatures high enough to endanger the players. So says a study of the 20-year meteorological record published in The International Journal of Biometeorology in January, which urges organizers to avoid afternoon kickoffs. Nine of the venues will probably experience a wet bulb globe temperature – a measure that combines the effects of the air temperature, humidity, solar radiation, and wind speed – above the safety threshold of 82.4F (28C) on more than half the afternoons of hot summers. The risks will be highest in half a dozen cities with open-air stadiums: East Rutherford, Foxboro, Kansas City, Miami, Monterrey, and Philadelphia. (An earlier study, published in October, made a similar prediction, forecasting “very high risk of experiencing severe heat stress conditions” in 10 of 16 venues.)
“The threat of extreme heat will be bigger at this World Cup than it was [at the 2022 World Cup in Qatar],” says Dr Donal Mullan, a climate scientist at Queen’s University Belfast and the lead author of the most recent study. “Some of these venues are kind of a disaster waiting to happen.”
The 2022 World Cup in Qatar was moved from the scorching summer months to November and December to protect the players. The highest wet bulb temperature – which is slightly different from wet bulb globe temperature – recorded during the World Cup in Qatar was 73.4F (23C) – a little less than 10 degrees below predicted figures in the US.
Fifa and US Soccer recommend that games implement cooling and hydration breaks when the WBGT exceeds 89.6F (32C). More cautious governing bodies, like the Australian federation, set a WBGT limit of 82.4F (28C) before matches can be delayed or even postponed. However, temperatures below those guidelines can still be dangerous. During the 2024 Copa América, held in the United States, an assistant referee collapsed from heat stress during a match in Kansas City when the WBGT was a mere 81.5F (27.5C). A few days earlier, defender Ronald Araujo had to be substituted out of Uruguay’s opening when WBGT reached the mid-80s, and the body’s physiological frailties were exposed. “The weakest link in the chain is going to break first and the heat will bring that about quickly,” says Dr Robert Huggins, a kinesiology professor at the University of Connecticut who worked with the US women’s national team and the Portuguese men’s team to prepare them to play in major tournaments in high heat. “From a thermoregulation perspective, the hotter the ambient temperature and the higher the humidity, the worse our body can dissipate the heat. If my sweat cannot evaporate off the surface of my skin and be accepted by the environment, I will not be able to physically cool my body.” game with Panama in Miami due to dehydration.
Kickoff times have not been announced for the 2026 World Cup yet, and Fifa did not respond to an email asking whether it would consider player safety in scheduling games and avoid afternoon kickoffs at its hottest venues.
“That’s the obvious answer, schedule it outside of these [afternoon] kickoff times,” says Mullan. “If you avoid those afternoon hours between 12 and 6 pm, that would make an enormous difference.”
The tournament’s expanded format will make that difficult. For most of the first two rounds of the group stage, there will be four matches a day. During the last round of group-stage matches, there will be six games a day. The round of 32 has five days with three scheduled matches. To maximize TV viewership around the world, a good number of those matches will probably have to be played in the afternoon heat.
The study Mullan authored was based on the summer temperatures from 2003 through 2022, which is to say, Mullan points out, that it represents a conservative estimate that did not incorporate the record heat in the summers of 2023 and 2024. Nor, for that matter, does it account for the possibility of wildfire smoke.
