It's called the Long John Index Service of Canada, and it works to keep Canadians warm all winter long.
There are no meteorologists or scientists involved, instead it's just a fun way of letting Canadians know when to pull out their thermal underwear, also known as "Long Johns."
"January 2010, the Long John Index Service of Canada came into being and it actually started as a joke. I started tweeting from it and weather nerds and people who like the weather, they really started to take to it and it has a small, but very loyal following," says Colin MacIntyre, Chief Intern with the Long John Index Service of Canada.
The Long John Index originated in Edmonton, Alberta and takes into account certain weather conditions including temperature and windchill.
It uses a scale which ranges from 1 to 5, with 1 being the lowest need to wear Long Johns and 5 being the highest.
"With a Long John index of 5, you don't go outside, keep your long johns on and put as many on as you can," laughs Colin. "Don't even go outside, put them on your kids, the cat, grab some hot chocolate, books or some comics and just curl up."
While The Weather Network relies on scientific methods for accuracy, Colin cautions against taking the Long John Index too seriously.
"It is for entertainment," he says. "If you really want to be getting the full weather forecast, you should be looking at The Weather Network because there are people that are far more trained than the Long John Index is to tell you about the weather."
For more on Colin's humourous take on weather, check out the Long John Index Service of Canada.