"How is a good weather forecast made? Or why Lothar sometimes falls through the cracks..." was the title of the lecture given by Germany's best-known "weatherman" Jörg Kachelmann at the University of Oldenburg on Monday, 25 January 2010. The ARD weather expert, together with Dr Martin Fengler, an employee of Kachelmann's company Meteomedia, gave an entertaining and informative insight into the development of a weather forecast to a packed auditorium in Wechloy.

Firstly, Jörg Kachelmann showed himself to be an experienced presenter and asked the audience about weather wisdom, farmers' rules and his own weather experiences. The "weatherman" dismissed all claims by the audience that, for example, thunderstorms do not cross the Weser or that thunderstorms are linked to high and low tides as pure superstition and therefore scientifically untenable. His explanations about the very widespread "weather beliefs", especially among the German population, were somewhat long-winded. Nevertheless, one always felt caught out when it came to the belief in bio-weather forecasts or the idea that the full moon has an effect on the weather. Kachelmann debunked these and many other popular rules about the weather as "pure nonsense", providing a great deal of entertainment for the audience of more than 300.

The more serious part of the lecture was then taken over by his colleague, Dr Fengler, who reported interesting facts about the importance of weather forecasts: current studies show that 70 per cent of the entire value chain depends on the weather and its influences. This is why attempts are being made to predict the weather more and more precisely, with the result that producing weather forecasts has become increasingly complex. The forecasts are based on thousands of measurement data as well as complex simulations carried out by huge computers. However, Fengler also pointed out the limits of today's forecasts, as even the large amount of data can only ever be an approximation of the current weather situation, which is the starting point for the forecast. And so, together with Kachelmann, Fengler also appealed for young talent: physicists are always needed to find better solutions.