Aeromancy
The art of foretelling future events by the observation of atmospheric, air or sky, phenomena. This goes beyond the range of weather prognostications, concentrating in such things as wind currents, cloud shape and formation, comets and falling stars, spectral formations, and other phenomena which are not normally seen or visible in the heavens. Even today such visions cause speculation and sometimes consternation among human viewers.
Some of the different forms of Aeromancy include Eromancy, Austromancy, Chaomancy, Roadomancy and Ceraunoscopy.
François de la Tour Blanche says that Aeromancy is the art of divining by means of specters which are made to materialize in the air, or the depiction by the aid of demons, of future events which are projected on the clouds as if by a magic lantern. For him, thunder, lightning and the aspect of the sky and planets belongs to astrology.