Scientists Warn That 26 of 104 World Cup Matches Will Likely Breach Hazardous Heat Thresholds

How Many Matches Are at Risk?

The WWA analysis reveals two critical danger levels. For 26 matches, the WBGT is projected to hit or exceed 26°C (79°F), the threshold at which the global players’ union FIFPRO says heat strain becomes a real risk and mandatory cooling breaks must be introduced . More alarmingly, there is a 1-in-3 chance that some matches will experience WBGT readings above 28°C (82°F)—a level that FIFPRO and several football governing bodies consider unsafe for play and where match postponement is advised .

The vulnerability is not distributed evenly. A separate peer-reviewed model found that 14 out of the 16 host locations surpass a WBGT of 28°C at some point during the summer, and four cities exceed that threshold more than half the time during afternoon hours in an average year. In the hottest year on record, nine host cities would cross that line more than 50% of the time .

Miami, Kansas City, and the Highest-Risk Venues

Not all World Cup stadiums face the same level of danger. The analysis consistently places Miami, Kansas City, Philadelphia, and New York/New Jersey at the top of the high-risk list, with Monterrey and Boston also flagged as concerning . The root causes differ by location. In coastal cities like Miami and Monterrey, the risk is amplified by brutal humidity that makes it exceptionally difficult for the body to dissipate heat through sweat . In Kansas City, the uncovered Arrowhead Stadium offers no shade for players or spectators, maximizing direct solar exposure .

The tournament final is scheduled for July 19 at MetLife Stadium in New York/New Jersey. The WWA calculates a 12% chance that this showpiece event will exceed the 26°C WBGT threshold, and a small but non-trivial 2.7% chance it reaches the level considered unsafe for play .

A Tournament Far Riskier Than 1994

When the United States last hosted the men’s World Cup in 1994, heat was a factor, but the baseline climate was fundamentally different. The WWA team found that human-induced climate change has made the kind of severe heat stress expected at this summer’s tournament roughly twice as likely as it would have been thirty-two years ago .

The shift is stark. Scientists no longer view extreme heat as an unpredictable outlier. The warming of the planet has fundamentally elevated the baseline, meaning that even “typical” summer conditions in many North American host cities now exceed established safety thresholds for prolonged, high-intensity outdoor activity .

FIFPRO’s Position and FIFA’s Countermeasures

The global players' union FIFPRO has been vocal about the escalating risks. Its recommended framework is clear: cooling breaks are essential when WBGT reaches 26°C, and matches should be delayed or postponed when WBGT exceeds 28°C . The union has publicly pushed FIFA to lower its own rescheduling threshold—which remains higher than FIFPRO’s guidelines at 32°C—and to rule out midday kickoffs in the most heat-prone cities entirely .

FIFA, for its part, has taken steps to address the concerns. The organization announced a blanket rule for the tournament: mandatory three-minute hydration breaks will be imposed midway through each half of every single match, regardless of the weather conditions, venue, or stadium roof . Additionally, FIFA conducted venue-specific heat risk assessments and adjusted the match schedule to limit daytime matches at outdoor stadiums, shifting many into evening slots or assigning them to air-conditioned venues such as those in Dallas, Houston, and Atlanta .

In Miami, where the Hard Rock Stadium lacks a full roof, kickoff times have been set no earlier than 5 PM local time . Yet critics argue these measures are incomplete. Several high-risk stadiums—Arrowhead in Kansas City, in particular—remain uncovered and unshaded, leaving players and fans fully exposed to direct sun during matches .

Performance and Broader Health Concerns

The risk extends beyond acute medical emergencies like heat stroke. A separate analysis by Climate Central found that climate change has increased the likelihood of performance-degrading heat for 97 out of the 104 scheduled matches . Temperatures above 82.4°F (28°C) are known to reduce sprint frequency, total distance covered, and recovery time, fundamentally altering match tempo and overall play style . For fans and stadium workers, the risk is no less real. Long periods of sedentary exposure in direct sun can lead to heat exhaustion, particularly for vulnerable individuals.

The Future of Summer World Cups

The 2022 tournament in Qatar was a landmark moment: FIFA moved the entire competition to winter specifically to avoid deadly summer heat. The WWA researchers question whether that lesson has been truly absorbed. With the 2026 tournament pinned to June and July, and no permanent shift away from the summer window announced for future events, the study authors warn that rising global temperatures “increasingly call into question the viability of hosting summer World Cups” in their current format .

Adaptation options do exist. Covered and climate-controlled stadiums, permanent night scheduling, or moving future tournaments to cooler months could all dramatically lower the risk . Without these changes, however, the consensus among scientists is unambiguous: summer World Cups will become progressively more dangerous, threatening not just the quality of play, but the safety of everyone who steps onto the pitch or into the stands .