How the North American heatwave could impact the FIFA World Cup 

Concerns about extreme July heat have hovered over the 2026 World Cup for months. Now, they’re becoming reality as the tournament collides with one of the hottest weeks of the year.

As a powerful “heat dome” settles over large parts of the United States and Canada, bringing with it furnace-like conditions and temperatures expected to exceed 43 degrees Celsius (110 degrees Fahrenheit) in several host cities, forecasters are warning about potential heat safety issues for some of this week’s knockout matches.

Which World Cup matches will be affected?

Toronto’s health authorities urged fans heading to Toronto Stadium for Portugal’s Round of 32 match against Croatia on Thursday to stay hydrated and limit their alcohol intake after Environment Canada issued a heat warning.

The city’s medical officer of health, Michelle Murti, said temperatures could feel like 40C (104F) because of the humidity.

Friday’s match between Colombia and Ghana in Kansas City will be played under an extreme heat warning, with “feels like” temperatures of up to 43C (110F). Miami, where Argentina face Cape Verde on Friday, is also expected to experience moderate to major heat risk this weekend.

Saturday’s match between Paraguay and France in Philadelphia could face similar conditions, with temperatures forecast to reach 39C (102F) and a heat index of up to 43C (110F). FIFA has already shortened the operating hours of its Fan Festival in the city because of the heat.

Which stadiums are most exposed to the heat?

Not all stadiums are created equal.

Stadiums in Atlanta, Dallas and Houston have retractable roofs and air conditioning, shielding players and fans once they’re inside.

But in Toronto, where the stadium capacity was expanded for the World Cup with a limited roof cover, around 43,000 fans will be exposed to the sun during Thursday’s match between Portugal and Croatia.

The same is true in Philadelphia and Kansas City, with capacities of approximately 68,000 and 69,000, respectively. Spectators will rely almost entirely on whatever shade, misting stations and cooling zones are provided by organisers, rather than any built‑in climate control.

Even when the match is indoors, however, the walk to the stadium can pose its own risks.

In Dallas, meteorologists warn that while the air temperature may be around 32C (90F), the pavement outside the stadium could reach 50C (122F). That means fans walking from car parks, train stations and fan zones could be much hotter than forecast.

“Concrete can actually absorb some of that heat,” National Weather Service meteorologist Jennifer Dunn said. “That will absorb and reflect that, and that can raise the temperature even more on those surfaces.”

How will the players be affected?

When the body overheats during intense exercise, the risks can become serious, even for elite athletes. Heat illness can cause dehydration, dizziness, cramping, headaches and extreme fatigue. In the most severe cases, it can lead to exertional heat stroke, a medical emergency and the third-leading cause of death in athletes.

The heat can also change the game itself. Players often sprint less, cover less ground and conserve energy, changing the pace and intensity of a match.

What is FIFA doing to protect players?

Every match now includes two mandatory three-minute hydration breaks, around the midway point of each half, no matter the weather or whether the game is played indoors.

The breaks have been controversial, with many fans, coaches and players arguing they disrupt the flow of the game and are a money-making opportunity for FIFA, giving broadcasters more time to air commercials. But FIFA President Gianni Infantino has rejected that criticism, saying “the main reason is the heat and that the organisation gains “absolutely nothing” from the breaks.

In addition to hydration breaks, teams can make up to five substitutions; there are at least three rest days between matches; and staff and substitutes at outdoor stadiums have access to climate-controlled benches.

FIFA said in April that the schedule was designed with the heat in mind.

“Outdoor matches during the hottest parts of the day have been strategically limited, kick-off times adjusted in certain markets and matches expected in warmer windows prioritised for covered stadiums where possible,” FIFA said.

This comes after last year’s Club World Cup in the United States, when the global players’ union, FIFPRO, warned that extreme heat should be a “wake-up call” for football.

How can fans stay safe in the heat?

Health experts recommend drinking water before you feel thirsty, taking breaks in the shade or air conditioning whenever possible, limiting alcohol and avoiding long periods in direct sunlight.

Medical teams will also be stationed at FIFA Fan Festival sites and around stadiums to respond to heat-related illnesses. Some host cities have also expanded access to shade, cooling areas and free water for fans and workers.

Experts say it’s also important to know the warning signs. Dizziness, confusion, severe fatigue or a lack of sweating can all signal dangerous heat illness. If symptoms become severe, medical attention should be sought immediately.