Reminds me of the opening to "Ministry for the Future" by Kim Stanley Robinson. In that book, a wet bulb event (high humidity and high temp) in India pushes infrastructure past the breaking point, the grid goes down, AC systems still running on generators are overloaded and overcrowded and fail, the water temp goes over body temp, and millions die. The positive cultural/societal reaction to the disaster strained my s…
The really scary thing will be when the wet bulb temperature goes above 35 degrees, and humans can only survive with AC.