If it’s August, it’s another issue of the Old Farmer’s Almanac that sends the internet’s collective mind into a tizzy. The much vaunted annual publication is famous for “accurately” predicting the weather (or so says your Aunt Erma), but it’s basically the print version of a psychic reading on a 1-900 number.

The Old Farmer’s Almanac is to meteorology what astrology is to astronomy. You know how you just can’t shake that confused, frustrated feeling when Mercury is in retrograde? (Oh wait, that’s in the book, too!) The long-range forecasts put out by the Old Farmer’s Almanac are like horoscopes—they’re just vague enough (and the forecast regions are just large enough) that the predictions appear accurate when applied to any situation.

The publisher asserts that the Old Farmer’s Almanac arrives at its forecasts using a secret formula that relies on, among other things, the activity of the sun and past weather:

We derive our weather forecasts from a secret formula that was devised by the founder of this Almanac, Robert B. Thomas, in 1792. Thomas believed that weather on Earth was influenced by sunspots, which are magnetic storms on the surface of the Sun.

Over the years, we have refined and enhanced that formula with state-of-the-art technology and modern scientific calculations. We employ three scientific disciplines to make our long-range predictions: solar science, the study of sunspots and other solar activity; climatology, the study of prevailing weather patterns; and meteorology, the study of the atmosphere. We predict weather trends and events by comparing solar patterns and historical weather conditions with current solar activity.

That “secret formula” is more than likely a reliance on climatology than anything else. If it’s snowed for four out of the past five years on February 11 in New York City, they’ll call for periods of snow during that week in February for the Northeast. Instead of predicting the weather, they’re looking at what’s happened in the past and banking on the fact that history will repeat itself.

The publication’s accuracy rate is highly debatable—they claim it’s 80%—but people swear by it, for better or worse (mostly for worse). After all, it’s hard to be completely wrong when you assert that snow will fall in the northeast during winter or that thunderstorms will develop in the southeast during spring. You can forecast using climatology with some accuracy, but you’ll often be wrong because the weather is rarely average. Averages are the products of extremes. A 15°F day in January and a 65°F day in January averages out to 40°F—if you were to use climatology and predict a high of 40°F on either of those days, you’d be way off.

The proliferation of this Potemkin Forecast is compounded by the fact that news organizations breathlessly report it as a scientific forecast like the ones issued by meteorologists using computer models. To that end, it’s funny how they only run wild with it when the “forecast” is for brutally cold and snowy conditions. A more cynical person would point out that news directors and editors know full well that the forecasts in the Old Farmer’s Almanac are better suited for fortune cookies, and it’s almost like they’re writing about it anyway to trigger a knee-jerk reaction in their readers so they spread the news widely on social media. Huh.

What does this winter really hold for us? It’s simply too early to say, which is something people don’t want to hear and the reason books like the Old Farmer’s Almanac sell so well. We want instant answers. We demand impeccable accuracy from our weather forecasts while also demanding weather forecasts for time periods for which it’s nearly impossible to say anything for sure either way.

The science of meteorology has advanced to the point where short term forecasts these days are incredibly accurate. A three-day forecast today is as accurate as a one-day forecast was back in 1980s, and it’s getting better all the time. Back in 2014, the Storm Prediction Center predicted a significant tornado outbreak in the central United States six days before it unfolded.

Long-range forecasts—months, not days, in advance—put out by meteorologists are far from perfect, but they’re much better than the paperback Magic 8 Ball that sits in a rack at the end of the checkout lane. You can predict general patterns—El Niño generally brings above-average precipitation to the southern United States, for example—but what actually happens is highly dependent on individual storm systems and the whims of the jet stream. You could predict a warm, dry winter based on long-range models, but if one storm accompanied by cold air dips far enough south that a few big cities get snow one night, people will consider the long-range forecast a bust even if the winter really was warmer and drier than normal as a whole.

During an El Niño winter, the southern United States would generally expect to see cooler and wetter (not necessarily snowy) weather, while the northern half of the country would normally stay a bit warmer than normal on the whole. That doesn’t mean there won’t be cold or snow in the north, nor does it mean there won’t be warm and dry periods in the south. It’s winter. Be prepared for snow and ice no matter what you hear in August.

It’s fun to think that you know what’s going to happen months before it actually happens. The Old Farmer’s Almanac is fun to talk about, but it’s not something you want to take seriously as so many are wont to do.

[Image: AP]

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