The Kansas City Royals were hot Wednesday at Wrigley Field, scoring an 8-4 road win.

So were the Cubs. And the umpires. And the fans. Everyone felt the heat in Wrigleyville.

Fans swarmed to the Addison Red Line station after the game, waiting as the humid 90-degree heat beat down on them. Riders in their sweat-stained Pete Crow-Armstrong jerseys squeezed onto the train, turning each car into a sauna room.

“If you wear a fur coat, you’ll die,” said Cubs fan Lee Kesselman, 73, while waiting in front of Gate 1.

Extreme summer heat during baseball season is not only making games uncomfortably hot and sweaty for fans in the stands — it’s also posing a danger to the health of players and changing the physics of the sport.

Since 1970, human-made climate change has driven up average summer temperatures in Chicago by 2 degrees, according to the climate science nonprofit Climate Central. That lines up with an average increase of 2.8 degrees across 26 Major League Baseball home cities in the United States — except Los Angeles. The home of the Angels and Dodgers has had no measurable change in baseball season temperatures since 1970.

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