A weather god or goddess, also frequently known as a storm god or goddess, is a deity in mythology associated with weather phenomena such as thunder, snow, lightning, rain, wind, storms, tornadoes, and hurricanes. Should they only be in charge of one feature of a storm, they will be called after that attribute, such as a rain god or a lightning/thunder god. This singular attribute might then be emphasized more than the generic, all-encompassing term "storm god", though with thunder/lightning gods, the two terms seem interchangeable. They feature commonly in polytheistic religions, especially in Proto-Indo-European ones.

Proto-Indo-European mythology is the body of myths and deities associated with the Proto-Indo-Europeans, speakers of the hypothesized Proto-Indo-European language. Although the mythological motifs are not directly attested – since Proto-Indo-European speakers lived in preliterate societies – scholars of comparative mythology have reconstructed details from inherited similarities found among Indo-European languages, based on the assumption that parts of the Proto-Indo-Europeans' original belief systems survived in the daughter traditions.