Why did the stadium get hot after the game? All of the fans left!
After the game, the stadium became hot as all of the fans had left. With the decrease in people, the temperature in the stadium rose significantly. The lack of bodies in the stadium caused the air to become stagnant and the heat to become trapped.
London Stadium is a multi-purpose outdoor stadium at Queen Elizabeth Olympic Park in the Stratford district of London. It is located in the Lower Lea Valley, 6 miles (10 km) east of central London. The stadium was constructed specifically for the 2012 Summer Olympics and 2012 Summer Paralympics, serving as the athletics venue and as the site of their opening and closing ceremonies. Following the Games, it was rebuilt for multi-purpose use and now serves primarily as the home of EFL Championship club West Ham United, who became anchor tenants from the 2016 season. UK athletics are the other tenants in the stadium and host a round of the World Athletics Diamond League each year, known as the London Grand Prix, sometimes called the London Anniversary Games.