How Does the Farmers' Almanac Work?

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Labor Day may have signaled the unofficial end of summer, but that milestone hasn't done much to cool off the regions that are still sweating in oppressively hot weather. There may be good news on the horizon for fans of chillier weather, though. The recently released 2016 editions of both the Farmers' Almanac and the Old Farmers' Almanac are predicting unusually frigid conditions across much of the country this winter. 

While these frosty predictions are fun to contemplate on steamy days, they raise an obvious question: How can an annual publication claim to know what this winter will be like months in advance, when my local weatherman can't even tell me with accuracy whether I’ll need my umbrella tomorrow?

The Secret Formula

Historically, almanacs are annual publications that outline the days of the year alongside factors like sunrise and sunset times, holidays, moon phases, and solstices. The calendar hanging on your wall is an example of a simple almanac. Some of the earliest almanacs referenced celestial events to tell readers whether they would have good or bad luck on certain days, much like how we use horoscopes today. By the 17th century, the only publication more popular than almanacs in England was the Bible. Around this time, they began popping up in the America colonies, offering seasonal weather predictions, tips for household management, and entertainment like puzzles and jokes.

The Farmers’ Almanac (founded in 1818) and the Old Farmers’ Almanac (founded in 1792) are two of the most popular remaining almanacs. The former offers long-range weather predictions made two years in advance. Today it claims to have an annual distribution of more than 2.6 million copies and a readership of 7 million.

Both publications claim to have a roughly 80 percent accuracy rate. Their predictions are the products of top secret mathematical formulas that take into consideration things like sunspot activity, tidal action, and planetary positioning.

Farmers' Almanac managing editor Sandi Duncan says the formula is so secret, even she doesn’t know it, and she’s been with the Farmers’ Almanac for more than 20 years. “I could probably access it if I gave away my first son or something.” The Almanac’s formula is entrusted to just one living being: a weather forecaster who, since the publication’s inception, has gone by the pseudonym “Caleb Weatherbee.” The Almanac’s editors keep everything about Caleb’s true identity a secret. In fact, the only thing they’re actually willing to confirm is that he exists. “He is a real person,” Duncan says. “We don’t want to let everyone know what his real name is. We don’t want anyone badgering Caleb. He’s got an important job so we have to make sure he can continue to do it. ”

An important job, indeed. The current Mr. Weatherbee is the 7th in the publication’s nearly 200-year history. He’s going on 25 years on the job and will likely remain in the position for life. How’d he land such a gig? Duncan says there was “something special in the stars.” Also, he loved weather, and was already a big fan of the Almanac. Being a Caleb Weatherbee takes a very special kind of person, Duncan says, “someone who probably looks beyond the computers and radar systems and appreciates that nature and the weather formula is a little bit more accurate at times for long range forecasts.”

And so we come back to the secret weather formula, which Duncan compares to the confidential concoctions guarded by KFC and Coca-Cola. “We gotta protect it,” she says. “We don’t want anybody figuring it out.”

The Prediction Problem

This is incredibly frustrating for skeptical scientists who, for years, have sought to put the formula to the test. “Anytime you have science that’s shrouded in secrecy or politics, something is not totally kosher,” says Jan Null, a certified consulting meteorologist with Golden Gate Weather Services. He began reviewing the accuracy rate of the Old Farmers’ Almanac in 2000 after seeing public officials like water managers base their decisions off its predictions. “It’s correct on the order of 25 percent to 30 percent of the time, which is no place close to the 80 percent of the time that is often claimed.”

Part of the problem, he says, is it’s nearly impossible to predict the weather with any kind of accuracy two years in advance, even with today’s advanced technology. “If someone really had the answer to that, think how incredibly rich they would be,” he says. “They would own the commodities market. That person is not out there. No one is showing good skill in long range weather forecasting.” Typically, he says, you can make weather predictions for the next seven days, but beyond that, your chances of being right plummet.

Duncan defends the Almanac’s efforts and cites its predictions for last winter. “We were very accurate,” she says. “We called for a very cold, very snowy winter.” But this is another problem with measuring the Almanac’s accuracy: Its predictions are so broad as to be nearly meaningless. In areas that experience it, winter is cold and snowy by definition.

Fact Checking the Formula 

But surely there is something about the Almanac’s methods that give it some credibility, right? Since I couldn’t get my hands on the actual formula, I asked a few scientists and meteorologists to explain how sunspot activity, lunar cycles, and planetary positioning impact seasonal weather predictions. Herein lies another problem: they don’t. At least, not significantly.

Let’s start with the planets: According to meteorologists with the National Weather Service, our elliptical orbit and the position of the planets has little if any effect on the weather. Here’s what they had to say, smiley face included: “...we are closest to the sun during the northern hemisphere winter, and this obviously does not prevent us from getting cold. :) There is also a slight wobble in the Earth's tilted axis, but the cycle of this wobble is extremely long, on the order of hundreds or thousands of years, and thus would have even less of an effect on seasonal weather conditions.”

What about the ocean tides? “Tides also don’t have any effect on the weather,” says Null. “Sea level goes up and down every six hours, that’s it.”

Of all the methods the Almanac admits to, sunspot activity is the only one scientists say could have some small effect on the weather. “Sunspot activity actually is slightly correlated with Earth's climate,” says Dr. Shane Keating, a physicist with a focus in atmosphere-ocean science.

Basically, the sun's magnetic field switches direction roughly every 11 years. During this period, the number of sunspots varies. Some evidence suggests that periods of fewer sunspots cause at least regional, and possibly global cooling. “However, the effect is fairly small compared with the natural variability of Earth's climate,” Keating says. And if there is an effect, it would be seen in terms of years or decades, not seasons, say NWS meteorologists. “Sunspot activity alone cannot accurately predict whether one's summer will be hot, winter will be cold, etc.”

Duncan admits the Almanac isn’t always right, and recommends people still listen to their local meteorologists. “We’re happy when our forecasts are on the mark, but of course sometimes they’re off the mark and we do admit that,” she says. “Mother Nature likes to remind all of us no matter what kind of weather formula we use to predict the weather that she’s in charge, and sometimes none of us can predict the weather with 100 percent accuracy.”