Aëromancy

Aëromancy (from the Greek: ἀήρ, aḗr ["air"] + μαντεία, manteia ["divination, soothsaying"]) is a method of divination based on the state of the air or atmospheric conditions. On the subject, T. T. Timayenis in A History of the Art of Magic (New York: J. J. Little, 1887), p. 24, relates the following:

This name was given to divination through certain appearances in the air. Besides the observation of meteors it included the study of the clouds, both those in process of formation and those that assume a variety of shapes; for it was believed that the cloud-forms foretold the happy and unhappy aspect of the planets. It was claimed that the four elements were peopled with spirits called sylphs, nymphs, gnomes, salamanders, etc. The gnomes were demons which lodged in the earth and were always intent upon doing mischief. Water was the home of the nymphs, while fire was that of the salamanders. The sylphs, peopling the air, were the most beautiful and lovable creatures in the world. We are told that one could easily approach them, yet on one condition, which rendered it well-nigh impossible — it was, to be absolutely chaste.

This method may be further sub-divided into: austromancy (wind); ceraunoscopy (thunder, lightning); chaomancy (aerial visions); and meteormancy (meteors, shooting stars).