Predicting the Weather

The Old Farmer’s Almanac is best known for its accuracy in predicting the weather some 16 months in advance of going on sale the second Tuesday of September. The 2007 edition, which is now available at most book stores, covers the period of October 2006 to December 2007. Would you like to learn what will happen this winter? Well, on page 184, the almanac says, “December through March will be colder than normal, on average, in all areas except northern New England, Florida, and southern Texas. Snowfall will be below normal in the High Plains, much of the eastern Great Lakes and the Southwest, near normal in the Ohio Valley, and above normal in other areas that normally receive snow.” Then turning to page 191, the following weather is predicted, “The coldest temperatures will be around Christmas and in early and mid- to late January and early and late February. The heaviest general snowfall will be in mid-December, early and late January and mid-February.” Let’s see how close their predictions are to the actual weather this winter. Last winter we know the Almanac was accurate in more than 99% of the country when forecasting snowfall.
The Almanac’s founder, Robert B. Thomas, was serious about his weather forecasting. How did he predict the weather? He devised what later became known as his “secret weather forecasting formula,” which still exists and is kept safely tucked away in a black tin box in Dublin, New Hampshire.

To predict the weather during the late eighteenth century the farmers would take into account nature’s signs, observing the thickness of the skin on onions, the width of stripes on the woolly caterpillar and the change from one moon phase to the next. Thus weather forecasting in 1792 was what you might call an imperfect science. Then Thomas came along with his formula based on a complex series of observed New England weather cycles. He also believed that weather on Earth was influenced by sunspots, which are magnetic storms on the surface of the Sun. In the 1793 preface, Thomas writes, “I need say but little; for you will, in one year’s time, without any assistance of mine, very early discover how near I have come to the truth.”
His formulas have been enhanced over the years by state-of-the-art technology and modern scientific calculations. Today the Almanac employs three scientific disciplines; solar activity, climatology, the study of prevailing weather patterns; and meteorology, the study of the atmosphere. Today the staff of the Almanac admits that they can not predict the weather with total accuracy, but claim that their predictions are almost always very close to 80%.

Snow in July

The dust from the 1815 eruption of Mount Tambora in Indonesia caused a worldwide lowering of temperatures during the summer of 1816. Legend has it that the Farmer’s Almanac correctly predicted snow for July. Some accounts say the printer inserted the snow prediction as a joke while Robert Thomas was sick in bed with the flu. When Thomas discovered the “error,” he destroyed all – or most of – the “snow” copies and denied making such a ridiculous forecast for the following summer. Then, when it really did snow in July, he took full credit. “Told you so!” he said.

Lincoln and the Almanac

In 1858 there was a murder trial of an Illinois man named William “Duff” Armstrong. He was accused of killing James Preston Metzker with blackjack a few minutes before midnight on August 29, 1857. Abraham Lincoln offered to defend the son of his friend, Jack Armstrong. The principal prosecution witness against Armstrong was a man named Charles Allen, who testified that he’d seen the murder from about 150 feet away. When Lincoln asked Allen how he could tell it was Armstrong given it was the middle of the night, Allen replied, “By the light of the moon.” Lincoln produced a copy of the 1857 edition of the Farmer’s Almanac and turned to the two calendar pages for August. He showed the jury that on the night of the murder the moon was in the first quarter and riding “low” on the horizon. Lincoln argued that there would not have been enough light for Allen to identify Armstrong. The jury agreed, and Duff Armstrong was acquitted.
World War II

In 1942 the FBI apprehended a German Spy on a train going into New York City’s Penn Station. The spy had landed on Long Island from a U-boat the night before and in the German’s coat pocket was the 1942 edition of The Old Farmer’s Almanac. Why were the Germans interested in the Almanac? (Did they like the jokes?) The U.S. government speculated that the enemy might be using it for the weather forecasts, so either the Almanac should be banned or the word “forecasts” should be eliminated. For the next four years the words “Weather Indications” were used. However, the Almanac was always of the opinion that it was the tide tables the Germans were interested in.