Sunshine and desert dust make the World Cup quarter-final in Miami a dangerous match for England and Norway

For a citizen of Norway For the men’s soccer team, Saturday’s World Cup quarter-final against England will be a first of its kind in more ways than one. As the Scandinavian side prepares for the biggest match in its history, they will also face almost unimaginable conditions in their homeland: the harsh mix of heat, humidity and blazing South Florida sunshine, which scientists warn can push the human body to its limits.

South Florida’s combination of strong sun, hot air temperature and high humidity – supported by a column of dusty air from the Sahara sweeping the Atlantic Ocean across the state – will put Nordic players under a level of heat stress rarely encountered in their home countries.

Scientists measure this heat stress by calculating the temperature of the WetBulb Globe. In addition to air temperature, the index takes into account humidity, which limits the evaporation of sweat from the skin; Wind, which can act as a coolant. And solar energy intensity, as sunlight directly raises the temperature of the skin and body.

Saturday’s game is expected to be played in extremely high temperatures of around 88 degrees Fahrenheit (31 degrees Celsius). The American College of Sports Medicine recommends stopping sports activities when this scale exceeds 82 degrees Fahrenheit, because at this level, a person has difficulty cooling down and the body temperature begins to rise quickly. FIFA itself states that if the WGBT temperature exceeds 90 degrees Fahrenheit, players and referees must take breaks after 30 and 75 minutes of play to cool themselves with a towel soaked in ice water.

While both teams were training to adapt to the environment, the conditions could make the match more sluggish, according to Matt Maley, a researcher in environmental ergonomics and exercise physiology at Loughborough University in the UK. “In Miami this weekend, we may see players reduce the number of sprints or the distance they cover,” he told WIRED. This will be a far cry from the fast-paced Premier League and lively elite matches that fans of English and Norwegian football are accustomed to watching.

But the real danger is ambition, Maley says. “Motivation sometimes replaces what the body is telling the brain, and that’s when we get into the danger zone, because people are motivated to run the same distance, do the same amount of sprints, and they could be setting themselves up for heat exhaustion.”

Miami, among other U.S. regions, has become hotter in recent years, as concrete and greenhouse gases released through burning fossil fuels trap heat.

A coalition of scientists from five continents warned participants in the FIFA World Cup and World Cup last May of the increasing medical risks resulting from heat stress. “We are concerned that current FIFA guidelines on heat stress mitigation are inadequate and will put players at risk of thermal injury at the 2026 Men’s World Cup,” they wrote in an open letter, noting that three-minute rest periods are too short for players to rehydrate and cool down. They recommended doubling hydration breaks and postponing any matches scheduled to take place with a WBGT temperature of 82 degrees Fahrenheit.

Fans also face risks, including heat exhaustion, dehydration and heatstroke caused by the stadium’s high heat stress levels, scientists from the New Weather Institute warned in a report, adding that older fans and those with pre-existing health conditions are particularly at risk. “The 2026 World Cup heat stress crisis threatens to turn what should be football’s greatest celebration into a public health emergency,” they warned.