weather-prophet

noun2

1. •
   A person who foretells the weather, especially without modern meteorological aids or knowledge.

   • They [...] are excellent weather-prophets; but they appear to think that they can add power to the natural phenomena by singing and performing ritual dances, and so on. — 1936
2. •
   An animal whose behaviour is an indication of coming weather, especially change of season.

   • "Diodorus," he says, "distinctly states that the hawk, in Egypt, was venerated because it foretold the future." (Birds generally act as weather-prophets.) — 1920