Greco-Roman meteorology will be described in four overlapping developments. In the archaic period, astro-meteorological calendars were written down, and one appears in Hesiod’s Works and Days; such calendars or almanacs originated thousands of years earlier in Mesopotamia. In the second development, also in the archaic period, the pioneers of prose writing began writing speculative naturalistic explanations of meteorological phenomena: Anaximander, followed by Heraclitus, Anaxagoras, and others. When Aristotle in the fourth century BCE mentions the ‘inquiry that all our predecessors have (...) been calling meteorology’ (338a26), he is referring to these writers. In the third development, the first two enterprises were combined: empirical data collection about meteorological phenomena began to be married to naturalistic theoretical explanation. This innovation was prompted by Democritus and synthesised in its most influential form by Aristotle. At this point more sophisticated techniques of both short-term weather forecasting and long-term speculation about global climate change were also developed. In the fourth development, the wider implications of the naturalistic explanation of meteorological phenomena were contested. The views of ‘meteorologists’ had been controversial since the archaic period because they were perceived, and sometimes intended, to displace the divine prerogatives and undermine traditional religion. These controversies intensified throughout the classical and Hellenistic periods. (shrink)