Farmers’ almanacs have predicted weather for centuries. Are they right about Florida’s winter?

In a New Hampshire town of about 1,600 people is a red-barn-style building. Inside, a staff of about a half-dozen work through the year to create a little yellow book with a cover that has been virtually unchanged for centuries — The Old Farmer’s Almanac.

Also in the building is a locked, black box that is said to hold the secret notes to the publication’s original ability to forecast the country’s weather months in advance.

“I’ve seen the box, I’ve never seen what’s inside,” Tim Goodwin, an associate editor for the Old Farmer’s Almanac, said.

Goodwin doesn’t know of anyone who’s seen inside the box, actually.

For 231 editions, since 1792, the Almanac has published the weather, poetry, moon phase charts, feature stories and recipes.

The Almanac says Florida’s winter will be “colder and rainier than normal.” That’s the opposite of the National Oceanic and Atmospheric Administration’s prediction made in October, which stated Florida would likely be warmer and drier than average this winter.

A spokesperson for the National Weather Service, an agency within the National Oceanic and Atmospheric Administration, said the service does not comment on private weather predictions.

The Old Farmer’s Almanac boasts a self-reported 80% average accuracy rate with its weather forecasts. Goodwin said the publication uses three tools for its weather predictions: solar science, climatology and meteorology.

“Obviously things have changed since 1792, and your ability to use technology and modern scientific calculations,” Goodwin said.

The Almanac’s website says their long-range forecasts stem from their age-old formula, however the formula has been enhanced “with state-of-the-art technology and modern scientific calculations.”

In a video posted to the website, editor-in-chief Jud Hale said his uncle likely inherited the black box with the formula when he purchased the publication in 1939. Hale said his uncle added in his own notes to the box.

“How far back it actually goes, if it goes to Robert B. Thomas, who founded The Old Farmer’s Almanac in 1792, I’m not sure,” Hale said. “But it’s old.”

An article by Discover Magazine references a study from 1981 that compared five years of The Old Farmer’s Almanac’s predictions against the recorded conditions in cities in the regions the Almanac covers across the U.S. At that time, the Almanac covered 16 regions; now it’s 18. According to the study, the Almanac’s forecasts were right about half the time, essentially just chance.

Regardless of the publication’s actual accuracy, it has remained a staple for some people today. More than 1.6 million people follow the Almanac on Facebook, and the Almanac publishes 2.5 million copies each year, according to the periodical.

The Old Farmer’s Almanac — originally just The Farmer’s Almanac — didn’t get “old” added to its name until around 1830, after other farmers’ almanacs had cropped up and folded, making it the longest running of the bunch. The Farmers’ Almanac, the plural possessive rival to The Old Farmer’s Almanac, first published in 1818 and still exists today.

“I think the thing about the Old Farmer’s Almanac is that it is one of those things that is passed down from generation to generation,” Goodwin said. “You know, grandparents passing it down to their grandchildren or parents to their children.”

Almanacs, not just the farmer kind, have existed in many capacities. An almanac is a book that contains events in a calendar year, like the moon phases or weather predictions, according to the Encyclopedia Britannica. A popular almanac of the 18th century, Poor Richard’s Almanack, written by Benjamin Franklin, also included recipes, conversion charts and proverbs, the Encyclopedia said.

Almanacs were the equivalent to a colonial smartphone — information at your fingertips, as described by The Atlantic.

In the 18th century, people started punching holes in their Old Farmer’s Almanacs to loop around their waistband, or hang in the kitchen or outhouse, so they would always be handy. The Old Farmer’s Almanac still punches holes in some versions at the top left corner of their paperbacks to continue the tradition.

The Farmers’ Almanac (the not “old” one) has published since 1818 and its content is much like the Old Farmer’s Almanac. The Farmers’ Almanac is predicting a “shivery, wet and slushy” winter for the southeast, including Florida. Peter Geiger, an editor for the Farmers’ Almanac, added a caveat that “slushy” only applied to the Carolinas and Georgia.

Geiger said there have been just seven weather forecasters in the publication’s history since the original, David Young. Young was a mathematician and astronomer who developed a formula that uses sunspot activity, planet positions and the moon to predict the weather, Geiger said. His formula has been passed down for nearly two centuries since his death.

“We do it two years in advance, and we’re not going to be right all the time, but I think we do a good enough job that people look to us when they’re planning a wedding, planning a vacation or whatever they might be doing,” Geiger said.

Paul Knight, a former Penn State meteorologist, spoke with the University in 2007 about the Farmers’ Almanac’s forecast accuracy. Knight pointed out that the Almanac makes blanket predictions, which makes its accuracy hard to assess.

“They say from November 5 thru 10, or that whole period: sunny/cool. If one day is sunny and cool, does that count? Does every day have to be sunny and cool?” Knight said to the university.

“If you want to use that for some kind of planting purpose or guidance more power to you,” Knight said. “And if it works for you, great. But will it work regularly? No.”

Both Geiger and Goodwin have said that their respective almanacs have grown past just being used for weather forecasts, or even just for farmers.

Geiger said weather is only a small portion of what the Almanac has in its pages.

“The weather is only like 8% of the pages,” Geiger said. “Weather is something that we do, however the Almanac itself is about life hacks. It’s about how to do things.”

Joseph Dalessio, the owner and operator of Meacham Urban Farm in Tampa, said he doesn’t subscribe to any farmers’ almanacs.

“I actually really haven’t done any kind of evaluation or research on how good the farmers’ almanacs are or anything like that,” Dalessio said. “But I mean, weather, it’s basically, it’s everything for farming.”

Dalessio said his farming is based on 100-year season patterns. Generally, Dalessio said they know when the last hurricane will pass through or when the first frost will happen. Dalessio said he knows when those seasons are changing and he does his best to plan around them.

Eric Gonyon, the owner of A Land of Delight Natural Farm & Nursery in Plant City, said he began in 2014 with a garden. The Old Farmer’s Almanac gave him the basis of his planting knowledge, which has helped him expand to a 6-acre farm, he said.

“I started the garden, and I didn’t know anything about it,” Gonyon said. “I didn’t even know what a grow zone was, I didn’t even know you couldn’t plant spinach in the summer.”

At first, he was skeptical. The book seemed more like fables to him. The almanac talked about not only growing by the seasons but by the phases of the moon.

“I started following it (the Old Farmer’s Almanac),” Gonyon said, “I figured, well, for hundreds of years if these farmers have learned through these trials and errors and through the moon and through seasons. So I started doing it and it actually works.”