What were temperatures on 4th of July, 1776 during signing of Declaration of Independence?

Philadelphia was a breezy 76 degrees on July 4, 1776, while America’s 250th birthday swelters under a dangerous triple-digit ...
The New York Times

What Exactly Is the Heat Index Anyway?

The metric of how hot the air actually feels has roots in a 1979 journal paper called “The Assessment of Sultriness.” By Andy Newman In recent days, you may have seen or heard many mentions of a ...