
With the progress of the World Cup qualifying phases, it is not just the pressure that is increasing. Temperatures too. “A record and dangerous heat wave will spread this week over the eastern two thirds” of the United States, warned the American Meteorological Service (NWS) on Tuesday on
This weekend, as Americans celebrate 250 years of their country’s independence, temperatures could exceed 38°C in most central and eastern states. “Numerous daily temperature records could be broken, while high overnight minimum temperatures of 70 to 80 degrees Fahrenheit will provide little relief, leading to ‘major’ to ‘extreme’ heat hazard conditions from the Midwest to the East Coast,” Thursday’s NWS bulletin warns.
At the height of the episode, the heat felt could reach between 40 and 46°C due to the very high humidity. Under these conditions, the holding of certain World Cup matches seems compromised. In Kansas City, the extreme heat alert issued by the National Weather Service will still be in effect this Friday at 9:30 p.m., when the city hosts the round of 16 match between Colombia and Ghana. Same scenario in Philadelphia, where France must meet Paraguay this Saturday at 5 p.m. for the eighth.
Cooling breaks during each half
Could the heatwave push the organizers to review the calendar? Or even move certain matches to cooler cities or to one of the three air-conditioned stadiums hosting matches? For the moment, Fifa has not taken any measures other than those announced before the event: implementation of a systematic refreshment break of three minutes per half-time; scheduling matches in the late afternoon and evening to avoid the hottest hours; provision of water, electrolyte drinks, ice, cold towels and misters for players.
But these measures are not enough to cope with very high temperatures, researchers warned in an open letter addressed to the federation in May. To reflect the human body’s ability to cool itself, they rely on the WBGT temperature index, also called the “wet bulb” temperature index. This unit takes into account the temperature, but also the sunshine or the wind. Indeed, an apparently moderate air temperature can, combined with humidity, become unbearable or even fatal: a high WBGT index of 28°C is equivalent to 38°C in dry weather or 30°C in very humid weather.
Vulnerability of players and spectators
Beyond 26°C WBGT, “even athletes who are well prepared and acclimatized to the heat are frequently unable to maintain thermal balance during intermittent high-intensity physical exercises,” underline these scientists who recommend, at a minimum, an extension of the cool-down break to six minutes. Their letter also warned of the vulnerability of the spectators, seated in the stands for long hours, and that of the workers participating in the organization.
But these alerts were obviously not heeded. The Guardian looked at the climatic conditions of the 72 group matches. Among them, two took place in extreme conditions which should, according to Fifpro, the union representing the players, have led to their postponement or cancellation: the meeting between Uruguay and Saudi Arabia on June 15 (1-1) then the one between Uruguay and Cape Verde, six days later. During these two matches organized at the Hard Rock Stadium in Miami, the thermometer would have been close to 33°C WBGT, according to the British newspaper. A value well above the limit of 28°C WBGT recommended by Fifpro.



