World Cup Matches in Miami and Monterrey Hit Severe Heat Levels
Two World Cup matches were played in ‘severe heat’, according to an analysis that found conditions exceeded thresholds that a football players’ union had previously warned should trigger delays or postponements. The Guardian analysis of the first 24 matches of the 2026 World Cup, which is being held across the United States, Mexico, and Canada, revealed that Saudi Arabia’s game against Uruguay in Miami had the most severe heat conditions. The second most severe conditions in stadiums without air conditioning occurred during Sweden’s match against Tunisia in Monterrey.
These games, despite being evening kick-offs, were played at wet-bulb temperatures of 28°C (82°F) or above, according to temperature and humidity data for the time and location. Fifpro, the global players’ union, has previously argued that games at 28°C or above should be delayed or postponed. When asked about the analysis, the union declined to comment on the heat situation at the tournament. This World Cup is forecast to be the hottest since the competition began in 1930.
Understanding Wet-Bulb Temperatures
Wet-bulb temperature is a measure of heat stress that combines air temperature, humidity, and cloud cover to determine how effectively the human body can cool itself through sweating. Beyond a certain threshold, sweat cannot evaporate properly, leading to rapid overheating that can cause illness or death. The Guardian used weather data from U.S. and UK government agencies and derived wet-bulb temperatures using a formula employed by authorities in several countries, including Australia and Canada.
To address the roasting North American summer, Fifa has moved some kick-off times to later in the day and introduced mandatory water breaks. A handful of the 16 World Cup venues have roofs or air conditioning that has mitigated some high temperatures. For example, England’s match against Croatia in Dallas saw fierce wet-bulb temperatures of nearly 35°C (95°F), but air conditioning inside the stadium reduced it to a more comfortable 22°C (71°F).
Six Matches Affected
In total, six of the first 24 matches were held in locations where wet-bulb temperatures hit 28°C or above: Germany vs. Curacao in Houston, Saudi Arabia vs. Uruguay in Miami, Portugal vs. DR Congo in Houston, the Netherlands vs. Japan in Dallas, and England vs. Croatia, also in Dallas. The stadium in Houston also has air conditioning. Record-high temperatures in some places caused fans to wilt in shadeless heat, and there are warnings that stadium workers, who often toil long before games with heavy equipment, face potentially hazardous conditions.
Current Fifa guidelines state that cooling breaks should occur if games are held in heat of 32°C (89°F) or above, though drinks breaks have occurred at lower temperatures during this World Cup. Delay or suspension of games is at the discretion of competition organizers. On the eve of the World Cup, a group of heat and public health experts urged Fifa in an open letter to implement more extensive heat protections, citing Fifpro’s call for games to be potentially called off at 28°C or above.
Expert Concerns
Robbie Parks, an environmental epidemiologist at Columbia University and a signatory of the open letter, said: “Temperatures are often taken from shaded areas, and if players are in direct sun, it can be double figures more than the temperature readings. Standing in the sun can be dangerous even at lower temperatures; even above 23°C (73°F) or 25°C (77°F) would make me concerned for older adults out there for more than a few minutes.” Parks noted that air conditioning, later kick-off times, and water breaks will help players, but further measures are needed for fans and workers. “Shade is super important and hydration is super important. You need to allow people to bring in their own water and think about having misters for evaporative cooling. The final is going to be held in New Jersey, and that stadium isn’t covered, which makes me worry. But I’d hope Fifa will learn the best way to deal with that by then.”
Extreme heat is the deadliest hazard worsened by the climate crisis, causing more deaths each year than hurricanes, floods, and wildfires combined. The World Cup tournament itself is set to add to the planet-heating pollution that is causing worsened heatwaves around the globe. The staging of more than 100 matches is expected to result in 7.8 million tonnes of greenhouse gases, double the amount of the previous World Cup in Qatar, according to estimates by Greenly, a global carbon accounting platform.
Fifa’s Response
A Fifa spokesperson stated that the governing body is “committed to protecting the health and safety of all players, referees, fans, volunteers and staff” at the World Cup. Fifa has stationed meteorologists at match venues to assist in preparing for extreme weather, and tournament planning includes “close coordination” with host city organizers, stadium authorities, and national agencies. Ahead of the tournament, Fifa agreed on a “tiered mitigation model” for extreme temperatures, with added interventions at different thresholds. For players, besides mandatory hydration breaks, there is access to water and electrolyte drinks, as well as other cooling tools including ice, cold towels, fans, mist, and shade.
For spectators, elevated temperatures mean match stadiums will “activate additional cooling capacity, including shaded areas, misting systems, cooling buses and expanded water distribution,” the Fifa spokesperson said. A medical set-piece protocol for treating heat exertion has also been introduced, with cooling bags set to be used for the first time. Fifa added that it will “continue to monitor conditions in real time, integrating wet bulb globe temperature and heat index surveillance, and stands ready to apply established contingency protocols should extreme weather events occur.”
