New Delhi, May 14 -- Around 25% of the 2026 FIFA World Cup matches are likely to be played in conditions of 26degC Wet Bulb Globe Temperature (WBGT), a heat index that includes temperature and humidity, or higher, a new analysis has warned, raising concerns over extreme heat and player safety.

The study said around five games could take place at WBGT levels of 28degC or above, which is equivalent to about 38degC in dry heat or 30degC in high humidity, a threshold that the global players' union FIFPRO considers unsafe for play and advises postponement.

Wet-bulb temperature combines heat and humidity measurements to indicate how effectively the human body can cool itself through sweating when outdoors. A wet-bulb temperature of 31 to 35de...