CHICAGO (CBS) -- We've been hearing that Chicago could be headed for a terrible winter. Now, the Farmers' Almanac is joining the chorus with some grim predictions.
CBS 2 meteorologist Megan Glaros takes a look at how the almanac comes up with its forecast.
It's always a battle royale of winter weather predictions.
Here's what the Farmers' Almanac says.
"It's going to be a kind of dicey winter," editor Phil Geiger says.
But Jim Allsopp of the National Weather Service says that's not a certainty.
"The thing is, it's very difficult to predict," he says.
The unpredictability is partly because of La Nina. It could bring cooler temps in the Pacific and lead to a harsher winter in Chicago.
The Farmers' Almanac forecast is based on a 'top secret' formula created by their original editor almost 200 years ago.
"He developed a mathematical formula which he applied to sunspot activity, planet positions, the effect that the moon has on the earth," Geiger says.
The farmer's almanac does claim and 80 percent to 85 percent accuracy rate, and they insist Chicago better get ready.
"It's gonna start in December, and it's just gonna keep going through the month of March," Geiger says.
But Allsopp, of the NWS, says there's "nothing that I can see that would indicate that Chicago would be necessarily any worse than any place else."
Still, it only takes one big blizzard to make it a really bad winter.
Average snowfall for Chicago is 38 inches. For the last four years, we've had over 50.
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