The Farmer's Almanac has made weather predictions for centuries, but how accurate are they? We checked in with an Earth scientist to find out.
Long before weather apps on mobile devices and weather reports on TV and in the newspaper, Americans relied on long-term weather predictions published in the Farmer’s Almanacs. Yes, that’s almanacs with an “s,” because throughout the 21st, 20th and most of the 19th century, there have been two of them. The original one is known today as the Old Farmer’s Almanac, and the newcomer is known simply as the Farmers’ Almanac.
Despite being two separate publications, both offer similar material. They give gardening advice, chronicle planetary movements, announce upcoming celestial events like meteor showers and discuss folklore and traditions in an entertaining way.
But the almanacs are probably best known for their long-term weather forecasts. The question is: How reliable are these forecasts really, especially in comparison to those provided by modern scientific methods? We asked Earth systems scientist Dr. Hansi Singh, who makes weather predictions her business, to weigh in.
What is the Farmer’s Almanac?
Almanacs are informational scrolls, booklets or pamphlets, and they are nothing new, having existed since at least the second millennium BCE. They publish lists of current and upcoming events, which makes them precursors to newspapers. In the Americas, Benjamin Franklin famously published Poor Richard’s Almanack from 1732 to 1758, which was a collection of weather forecasts, puzzles, practical hints and other entertainment. It had an annual print run of 10,000 copies.
Robert B. Thomas published the original Farmer’s Almanac primarily for farmers (as you might have guessed). Its purpose, in part, was to help people who relied on crops for survival maintain their farms and plan their planting based on the expected weather conditions for the year. However, this almanac, which had to compete with similar ones, strove to offer advice that was “new, useful and entertaining,” and this has helped cement its popularity throughout the years.
When was it started?
The Farmer’s Almanac started as a regional publication in 1792. Thomas first published it in Massachusetts, and he maintained editorial control until his death in 1846. In 1818, David Young and Jacob Mann of New Jersey published a different version that proved to be just as popular. In 1848, the original version founded by Thomas became officially known as the Old Farmer’s Almanac, while the one introduced by Young and Mann became simply the Farmers’ Almanac. Both have been available to the public continuously since then.
How does it work?
Like the formulas for Coke and KFC, the exact method the Almanacs use for making long-term weather forecasts is a closely guarded secret. In general, says Singh, “the Farmer’s Almanac creates its forecasts largely on historical weather patterns in addition to factors like sunspot activity and even astrology.”
That puts it in a nutshell as far as the original almanac goes, except maybe for the astrology part. According to its website, the Old Farmer’s Almanac uses three disciplines to make its predictions, and it doesn’t mention astrology. The Farmers’ Almanac, however, devotes an entire section to astrology in its website, so it is the more likely of the two to incorporate astrological considerations into its predictions.
The disciplines the Old Farmer’s Almanac claims to use to make its weather predictions are:
- Solar science: the study of sunspots and other solar activity;
- Climatology: the study of prevailing climate patterns;
- Meteorology: the study of Earth’s atmosphere.
How Accurate is the Farmer’s Almanac?
This is a matter of debate. The Old Farmer’s Almanac claims a traditional accuracy of 80 percent, but a study conducted by the University of Illinois over a five-year period and published in 2010 found the accuracy to be more like 52 percent — in effect, a coin toss. Nevertheless, because the Almanac’s predictions rely in part on celestial phenomena unaffected by the Earth’s ever-changing atmosphere, they can be uncannily accurate at times, which may be why they remain popular, despite being considered by many, including Hansi, to be unscientific.
Is the Farmer’s Almanac Less Accurate Than Other Weather Predictions?
That would be yes, according to Singh. “Earth scientists have developed long-range weather prediction tools over the last two decades that rely on sophisticated Earth system models. These models integrate the atmosphere, ocean, land, and ice — the key drivers of Earth’s climate — to extend forecasting skill beyond the 10-day weather window.
Unlike the Almanac’s approach, modern science-based forecasts also incorporate the impacts of climate change, which historical pattern-matching cannot capture.”
Best Long Range Weather Predictions
The chaotic nature of Earth’s atmosphere makes long-term weather prediction difficult, but as Singh mentions, new climate models make long-term forecasting more reliable.
“The most trusted long-range forecasts come from major scientific agencies such as NOAA in the U.S. and ECMWF in Europe, both of which make their data publicly available,” she says.
In addition, Singh points to Eddy, an AI tool available at her website Planette that promises forecasts that are right 95 percent of the time. “At Planette, we provide localized forecasts through Eddy that have been shown to outperform both NOAA and ECMWF on key measures of accuracy.”
I just tried Eddy, which can make forecasts as far ahead as four months. I hope its claims of accuracy are true, because for 2025 it predicts a cool, dry and pleasant autumn in the part of California in which I live. That will be a fitting capper to an extremely pleasant summer in this part of the world, so let’s see if Eddy nails it.
FAQ
What other info is in the Farmer’s Almanac?
If you’re online, you can go to either the Old Farmer’s Almanac site (almanac.com) or the Farmers’ Almanac site (farmersalmanac.com) to find weather predictions, advice on gardening and food preparation, handy household tips and information on the movements of the sun, moon and planets. You’ll also find calendars that advise on the best days to conduct certain activities. The Farmers’ Almanac site also has sections devoted exclusively to astrology and folklore, which I didn’t find on the Old Farmer’s Almanac site.
You can also find paperback and hardcover versions of both almanacs at bookshops and newsstands. They contain much of the same information you’ll find online.
When is the Farmer’s Almanac published?
The Old Farmer’s Almanac and the Farmers’ Almanac are published every year in late August or early September.
About the Expert
- Dr. Hansi Singh is an Earth systems scientist, mathematician and CEO of Planette, a company delivering long-range weather forecasts.
Sources
- Almanac: How The Old Farmer’s Almanac Predicts the Weather; (2025)
- Almanac: Difference Between The Old Farmer’s Almanac and Other Almanacs; (2025)
- Popular Mechanics: How Accurate Is the Farmer’s Almanac? Here’s What Research Says; (2022)
- Planette: Eddy; (2025)
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