Vilhelm Bjerknes (1862–1951), a Norwegian physicist and meteorologist, was the author of the first formal studies on weather forecasting. He was also famous for his seminal 1921 book, *On the Dynamics of the Circular Vortex with Applications to the Atmosphere and to Atmospheric Vortex and Wave Motion,* which proposed the fundamental ideas behind numerical weather prediction in 1904. The theory was picked up again in 1922 by English mathematician and meteorologist Lewis F. Richardson (1881–1953). The mathematics behind Bjerknes’s theory appealed to Richardson, but the calculations necessary to come up with the predictions, in a time before the invention of the computer, were formidable. Richardson estimated it would take a coordinated effort of about 26,000 people using calculators to figure out the math fast enough for the numerical method to work. Trying to do some preliminary calculations himself, Richardson’s early attempts at weather predictions were far off the mark. His misunderstanding of some of Bjerknes’s numerical methods led him to come up with estimates on air pressure that were far too high. Because of Richardson’s failure, numerical weather prediction was abandoned until the 1940s.