For millennia, as long as humans have walked the Earth and experienced the elements, there's been no official criteria used to determine when the weather is "hot as balls" or "colder than a witch's tit." But now, granted by the ease and sophistication of modern technology, we finally have a good sense of the exact temperatures that give these expressions real life.
Jim Webb, a Washington, DC-based web developer and hero of the vernacular, made a tool that correlates descriptions of the weather with geo-located tweets. Mashable first noticed the project on Github, where Webb describes his hot-as-hell methodology, writing: "5,400 geolocated tweets with phrases like 'it's hot as hell' or 'it's cold as a bitch' were collected from August 2017 to January 2018, and the outdoor temperature collected for each."
The project essentially geo-tagged the locations of various users who were tweeting about the weather, and correlated their expressions -- "cold as balls" (37 degrees) and "hot as shit" (86 degrees) -- with the weather. The temperatures you're seeing below are the median temperatures ascribed to each phrase. They'll be familiar to anyone who's ever cursed the sun on a scorching day, or shivered cold and alone after an evil landlord turned off the heat.