Actually it is related to the air conditioning. Prior to AC, the subway and its platforms were cooler than the outside. Still not pleasant on a 100 degree day,

Actually it is related to the air conditioning. Prior to AC, the subway and its platforms were cooler than the outside. Still not pleasant on a 100 degree day, but certainly not as it is today: the platform will be significantly hotter than outside. Just gotta survive long enough to board the train. https://cityroom.blogs.nytimes.com/2008/08/08/complaints-about-hot-platforms-as-old-as-the-subway/?mcubz=1 https://cityroom.blogs.nytimes.com/2008/08/08/complaints-abo...