The Conclusion traces the importance of astrometeorological forecasts from the seventeenth century onwards. It finds surprising evidence that they finally disappeared only in the nineteenth century, despite increasing criticism. In fact, one of the attackers mourned the continuing high sales of Moore’s almanac in the 1830s. A central finding is that the increasing rejection of astrology in the eighteenth century, and the attacks on astrometeorology, led to the absence of any accepted basis for making weather forecasts. This problem, together with ongoing demand for knowledge of coming weather, led to the revival of old-fashioned weather-signs. The support given by Tycho Brahe and Johannes Kepler to both astrometeorology and the keeping of waether records is considered, as are early modern treatises on weather prediction. A detailed study of English 18th-century almanacs shows use of weather journals and instruments such as barometers, alongside traditional astrometeorological methods. The final conclusion is that it was only the production of FitzRoy’s new, ‘practical’ system of forecasting the weather that finally ended the age of medieval meteorology.

Chapter 8 sets out the evidence for the growing prestige of, and demand, for, astrometeorological forecasts in the fifteenth century. It traces the establishment of chairs in astronomy and astrology in universities old and new across Europe, and looks at the forecasts issued by the holders. The rapid creation of annual almanacs, based on these forecasts, and the demand for affordable, printed copies, are outlined. The important works of Abraham Zacut, Regiomontanus, the Laet family, and Leonard Digges, are all discussed in detail. The numbers of printed editions, their price levels, and their success, are all considered as evidence of demand for updated, ever more accurate, versions of astrometeorology. Digges’ work is shown to have addressed a readership keen to make their own forecasts. The conclusion is that it was in the sixteenth century that astrometeorological weather forecasts reached their peak, even though changing intellectual fashions saw shifts in the great names claimed as founders of the science. Moreover this popularity was to last well into the seventeenth century.