Research by World Weather Attribution (WWA), a global climate science network, finds that extreme heat and humidity are more likely across several host cities in the United States, Canada and Mexico compared with past tournaments, largely because of human-driven warming.

The World Cup, scheduled from 11 June to 19 July 2026 across 16 cities, will see a wide range of climatic conditions due to its vast geographic spread. Northern and coastal venues are expected to have milder conditions, while inland and southern sites are forecast to endure significantly higher temperatures, often exceeding 30°C, especially during daytime play.

Scientists say that a commonly used heat stress measurement, the Wet Bulb Globe Temperature (WBGT), could rise above levels considered safe for strenuous outdoor sport for many matches. Historically used thresholds suggest that at 26°C WBGT players and officials should take extra cooling breaks, with 28°C and above seen as unsafe for continued play.

According to the analysis, around a quarter of the tournament’s matches could be played in conditions where WBGT exceeds these thresholds — a sharp increase compared with the 1994 World Cup in the U.S., when extreme heat was less widespread.

Organisers have introduced measures such as mandatory three-minute hydration breaks each half to help protect players, but experts warn these may not be sufficient given the elevated risk from climate change.

With kickoff less than a month away, scientists and player welfare organisations continue to urge FIFA to closely monitor conditions and adapt scheduling and safety protocols where necessary to minimise risks stemming from extreme heat.