The 2025 Club World Cup in the United States presented players with challenging conditions due to high temperatures.
A coalition of leading scientists has cautioned FIFA that its current heat safety protocols for the 2026 Men’s World Cup are “inadequate” and could expose players to significant health risks.
In an open letter, external, international experts in health, climate, and sports performance assert that the governing body’s guidelines are inconsistent with current scientific understanding and “impossible to justify.” They are urging FIFA to implement more robust protective measures, including extended cooling breaks and clearer guidelines for delaying or postponing matches under extreme conditions.
Heat is anticipated to be a significant factor at this summer’s tournament across the United States, Canada, and Mexico, with researchers projecting that temperatures at 14 of the 16 stadiums could exceed safe levels.
Across parts of the southern U.S. and northern Mexico, average daytime highs typically range from the low to mid-30s Celsius and can approach 40C during hotter periods.
Factoring in temperature, humidity, wind speeds, and solar intensity, players in these World Cup host cities face a heightened risk of experiencing extreme heat stress.
FIFA maintains it is “committed to protecting the health and safety of players, referees, fans, volunteers, and staff” and that climate-related risks are incorporated into tournament planning.
How could extreme weather affect World Cup 2026?
As part of its “commitment to player welfare,” FIFA has mandated three-minute cooling breaks in each half of every match, irrespective of weather conditions.
Climate-controlled benches will be available for technical staff and substitutes at all outdoor matches.
FIFA also employs the Wet Bulb Globe Temperature (WBGT), the gold-standard heat measure for sports, which assesses physical heat stress by combining heat and humidity. A WBGT of around 28C is widely recognized as the threshold at which heat stress becomes a significant concern for elite athletes.
According to FIFA’s emergency care manual, external, when the WBGT reading approaches, reaches, or exceeds 32C, match organizers should agree on “what precautions need to be taken to prevent any heat-related illness from occurring.”
FIFA states it also has measures for fans at matches “when forecasts indicate elevated temperatures.” Spectators may bring a factory-sealed water bottle, and venues will activate additional cooling measures, including shaded areas, misting systems, cooling buses, and expanded water distribution.
The letter has garnered signatures from 20 world-leading scientists.
The signatories comprise leading academics from the UK, USA, Canada, Australia, and Europe.
They are advocating for FIFA to urgently revise its approach, including:
Delaying or postponing matches above 28C WBGT.
Implementing longer cooling breaks of at least six minutes.
Enhancing cooling facilities for players.
Regularly updating guidelines based on the latest scientific findings.
They also urge FIFA to adopt standards proposed by global players’ union FIFPRO.
Andrew Simms, director of the New Weather Institute, who coordinated the letter, told BBC Sport: “Player safety is an immediate and urgent concern because things can go wrong very quickly when people overheat.”
“We’re worried that Fifa is playing recklessly with the health and safety of players.”
Another signatory, Professor Douglas Casa from the University of Connecticut, stated that much of FIFA’s current guidance is far from ideal: “The hydration break in each half absolutely needs to be longer than three minutes – at least five minutes for each break and preferably six.”
“We hope this open letter convinces Fifa to update its heat guidelines before the World Cup.”
Extreme weather is expected to be a factor at the 2026 World Cup. Heat, thunderstorms, and even poor air quality from wildfires are all features of summer across the United States, Canada, and Mexico, where the tournament will be held.
New analysis from the World Weather Attribution (WWA) reveals players and fans face a much higher risk of grueling heat and humidity at the tournament compared with the 1994 World Cup on the same continent.
Scientists found around a quarter of matches are likely to be played above 26C WBGT, while about five games could exceed 28C WBGT (equivalent to about 38C in dry heat, or 30C in high humidity), a level that FIFPRO considers to be unsafe for play.
The WWA says the risk of more extreme conditions has nearly doubled since 1994 due to climate change.
FIFA declined to comment directly on the letter or the scientists’ claims but said it would use a “tiered heat mitigation model” at the tournament, with measures adapted to real-time conditions.
A spokesperson stated there would be dedicated meteorological support throughout the competition, both centrally and across host cities, with WBGT and heat index monitoring informing decision-making.
They added that scheduling had been designed with climate in mind, with kick-off times adjusted, matches during the hottest periods limited where possible, and warmer fixtures prioritized for covered stadiums. The schedule, FIFA said, also aims to minimize travel and maximize rest days based on location-specific heat risk assessments.
FIFA stated it would continue to monitor conditions in real-time and apply contingency measures where necessary, adding it is working with host authorities and medical experts to ensure a “safe and resilient” tournament.