The Long John Index is a not scientific whatsoever method of measuring when, and if, one should be wearing a pair of thermal long underwear, known more commonly in the Dominion of Canada as “Long Johns.” The Long John Index originated in the Arctic Capital of Edmonton Alberta, in the second decade of the 21st Century. It is used mainly for edutainment and gambling purposes.Oh, well when you put it that way, its really quite simply not simple at all. The Index runs on a scale from 1 to 5; 1 being the lowest, and 5 being the highest. The Index corresponds to weather conditions, including air temperature as well as that Wind Chill, which was invented so people can brag about living through -68 degrees, even though it was really only -31 degrees. The Higher the number ( or rating if you will ) the more your very survival depends on wearing a pair of Long Johns.Long Johns shouldn’t be needed, unless one is spending 7+ hours outside with no toque and standing so still they might be mistaken for one of those creepy living mannequins. Any movement will generate enough body heat to not need Long Johns. Hell, blinking will generate enough body heat to keep you warm. If you are wearing them at this temperature, hang your head in shame, and go back to Vancouver.