Aeromancy is divination by observing atmospheric phenomena.
Ceraunomancy is divination by observing lightning. Ancient Roman augurs believed that lightning bolts from the east were favorable omens, while lightning bolts from the west were bad omens. Lightning bolts from the north were the worst omens. Lightning bolts from the northwest were a sign that very bad news would arrive soon.
Ceraunoscopy (also called keraunoscopy) is divination by observing thunder and lightning. Ancient peoples believed that thunder and lightning were direct communications from the gods and goddesses, such as Thor (thunder) or Zeus (lightning). The Hindu, Etruscans, and Babylonians made extensive use of ceraunoscopy.
Tinia, the Etruscan god of lightning, was particularly associated with ceraunoscopy. Similarly, Adad, the Babylonian god of thunder, lightning, and prophecy, was particularly associated with ceraunoscopy.
François de la Tour Blanche “As for thunder and lightening these are concerned with the auguries, and the aspect of the sky and of the planets belong to the science of astrology.”
In the Middle Ages, Europeans believed that thunder and lightning were omens of coming war, floods, or the death of an important person.
See also: divination and aeromancy.
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