The Weather Notebook: The First Computer Forecast

The First Computer Forecast
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Hi, I'm Dave Thurlow and this is The Weather Notebook. Fifty years ago this Sunday, modern weather forecasting began. It was at noon on March 5, 1950, that the first computerized weather model began going through its paces. This historic event took place on the world's first-ever electronic computer. The machine was called ENIAC, which stood for electronic numerical integrator and computer.

The ENIAC, in BRL building 328. U.S. Army Photo - K. Kempf
ENIAC was founded at the University of Pennsylvania during World War II. It was then moved to an Army research lab in Maryland. There, it began doing weather forecasts with the help of a team from the Institute for Advanced Study at Princeton.

ENIAC was certainly different from today's blistering supercomputers. The machine had almost no internal memory, so most of the calculations were done on punch cards that were fed back to ENIAC for its next round of number-crunching. A single 24-hour weather forecast required about 25,000 of these punch cards!

ENIAC was no speed demon, either. The first 24-hour forecasts took just about 24 hours to make. And all this work produced forecasts for just one level of the atmosphere above North America. Still, there were promising signs. Two of the first four outlooks showed some degree of accuracy. Faster computers would soon allow the forecasts to be done in time to be useful. By the mid-1950s, a number of countries were experimenting with pioneer computers to make their own weather forecasts. The rest is, as they say, history--although weather and climate are still such complicated problems that they challenge even the best supercomputers of today.

Thanks to contributing writer Bob Henson and for more information, be sure to visit our website at weathernotebook.org. The Weather Notebook is underwritten by Subaru, the beauty of all wheel drive.