The recent tornado outbreak in the Plains States was predicted by forecasters at the Storm Prediction Center in Norman, Okla., as far as seven days in advance. This kind of forecast undoubtedly contributed to a vigilance that resulted in only six lives being lost in this first major outbreak of the year.
Such forecasts are the product of an enterprise known as Numerical Weather Prediction (the forecasting of the weather by means of computer calculations). Though forecasting the weather has long been a dream of humankind, NWP is a very recent invention.
Perhaps the first thinker to consider the real possibility of forecasting the weather by calculation was the 14th century French mathematician, Nicole d’Oresme, who considered it possible if only the “proper rules” were discovered. These “rules” were the laws of physics discovered by Isaac Newton some 300 years later.
The first real attempt at calculating the future weather was made by Lewis F. Richardson, an English Quaker who, while between ambulance runs in France during WWI, wrote his great book, “Weather Prediction by Numerical Processes,” in which the first forecast by calculation was an utter failure.
His ideas were not taken up again until the early 1950s, after the invention of the computer. In fact, modern computers were arguably first tested on the problem of weather prediction through the efforts of professors Jule Charney (MIT) and John von Neumann (Princeton). They were the brains behind the so-called Joint Numerical Weather Prediction Unit, which issued its first daily forecast on May 6, 1955.
Through the efforts of many outstanding meteorologists and computer scientists in the intervening 57 years, weather prediction (informed by expert interpretation of the computer output at the core of NWP) has advanced enormously to the point where the three- to five-day forecast is nearly as accurate today as the one-day forecast was in 1975. Such advances certainly saved lives in the tornado outbreak of April 14.
