World Cup Faces Dangerous Heat as Players’ Union Calls for Action

The World Cup always promised to be hot. Few expected the tournament to start with games played in conditions a leading players’ union has said should trigger delays or postponements.

Yet a Guardian analysis of the first round of group matches – 24 games, each team’s opener across the US, Mexico and Canada – shows two fixtures were played in heat so severe they crossed the warning line set by Fifpro, the global players’ union. Four more hit that level in the host cities, with only stadium air conditioning dragging conditions back from the edge.

The most punishing? Saudi Arabia v Uruguay in Miami. Sweden v Tunisia in Monterrey ran it close. Both evening kick-offs. Both played in wet-bulb temperatures of 28C (82F) or higher in stadiums without air conditioning.

That 28C mark is no arbitrary number. Fifpro has previously argued that matches hitting that threshold should be delayed or postponed. Asked about these findings, the union declined to comment on the current World Cup. The backdrop is stark: forecasts suggest this will be the hottest World Cup since the competition began in 1930.

What the numbers really mean

Wet-bulb temperature sounds like a technicality. It is not. It is a measure of heat stress that blends air temperature, humidity and cloud cover to show how effectively the body can cool itself through sweating.

At a certain point, sweat simply stops doing its job. It no longer evaporates fast enough. The body overheats, and it does so quickly. That is when heat illness, and in extreme cases death, enters the conversation.

To assess conditions, the Guardian drew on weather data from government agencies in the US and UK, then calculated wet-bulb values using a formula employed by authorities in countries including Australia and Canada. The picture that emerges is of a tournament pushing up against the limits of safe play.

Fifa’s response has been to shuffle kick-off times, push more games into the evening and enforce mandatory water breaks. A handful of the 16 venues have roofs or full stadium air conditioning, softening the blow in some locations.

Dallas, Houston, Miami: the early hotspots

The list of early flashpoints is revealing. Six of the first 24 games took place where the wet-bulb temperature hit 28C or above:

• Germany v Curacao in Houston
• Saudi Arabia v Uruguay in Miami
• Portugal v DR Congo in Houston
• Netherlands v Japan in Dallas
• England v Croatia in Dallas
• England v Croatia again counted in the analysis as one of the highest indoor–outdoor contrasts

Houston and Dallas both have air-conditioned stadiums. That infrastructure has already been tested.

On Wednesday in Dallas, England faced Croatia in what, on paper, were the fiercest wet-bulb conditions of the tournament so far – close to 35C (95F) outside. Inside, the stadium’s air conditioning hauled that down to around 22C (71F), a figure more in line with a mild European spring than a Texan summer.

The contrast outside the controlled bowl was brutal. Record temperatures in several host cities have left fans wilting in open, shadeless concourses. Stadium workers, many hauling heavy kit for hours before kick-off, are exposed for far longer than the players and face what experts describe as potentially hazardous conditions.

Fifa’s current guidelines call for cooling breaks when the temperature hits 32C (89F). In practice, referees have been stopping play for drinks at lower readings during this World Cup. Any decision to delay or suspend a match rests with the competition organisers.

Experts warn: “Standing in the sun can be dangerous”

On the eve of the tournament, a group of heat and public health specialists wrote an open letter urging Fifa to go further, explicitly backing Fifpro’s call for games to be halted once wet-bulb temperatures reach 28C.

Robbie Parks, an environmental epidemiologist at Columbia University and one of the signatories, underlined the gap between official readings and lived reality.

“Temperatures are often taken from shaded areas and if players are in direct sun, it can be double figures more than the temperature readings,” he said. “Standing in the sun can be dangerous even at lower temperatures, even above 23C (73F) or 25C (77F) would make me concerned for older adults out there for more than few minutes.”

For players, Parks acknowledges that air conditioning, later kick-offs and water breaks will help. He is far less relaxed about those in the stands and those working around them.

“Shade is super important and hydration is super important,” he said. “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.”

Climate crisis sits in the background – and on the pitch

All of this is playing out against a wider, unavoidable context. Extreme heat is already the deadliest climate-related hazard on the planet, killing more people each year than hurricanes, floods and wildfires combined.

The tournament itself will add to the problem. More than 100 matches across three countries means more flights, more travel, more energy use. Greenly, a global carbon accounting platform, estimates this World Cup will generate around 7.8m tonnes of greenhouse gases – roughly double the emissions linked to the previous edition in Qatar.

So the competition is not just threatened by the climate crisis. It is also helping to drive it.

What Fifa says it is doing

Fifa insists it is alive to the risks. A spokesperson said the governing body is “committed to protecting the health and safety of all players, referees, fans, volunteers and staff” at the World Cup.

Meteorologists have been stationed at match venues to track conditions and advise on preparations for extreme weather. Tournament planning, Fifa says, involves “close coordination” with host cities, stadium operators and national agencies.

In the build-up, Fifa signed off a “tiered mitigation model” for extreme temperatures, a sliding scale of interventions that escalate as conditions worsen.

For players, that means mandatory hydration breaks, access to water and electrolyte drinks, and a suite of cooling tools: ice, cold towels, fans, mist and shade. On the medical side, a specific protocol for treating heat exertion is in place, with cooling bags set to be used at a World Cup for the first time.

Spectators are promised more help when the mercury rises. According to Fifa, elevated temperatures will trigger extra cooling capacity at stadiums – shaded zones, misting systems, cooling buses and increased water distribution.

The governing body says 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.”

For now, the tournament rolls on through a North American summer that feels less like a backdrop and more like a central character. The question is no longer whether heat will shape this World Cup, but how long football can keep sprinting into conditions its own experts say should stop the game.