astrometeorology

from The Century Dictionary.

• noun The pretended art of foretelling the weather and its changes from the aspects and configurations of the moon and stars: a branch of natural astrology.
• noun Prognostication of the weather from the appearance of the heavenly bodies.

from the GNU version of the Collaborative International Dictionary of English.

• noun The investigation of the relation between the sun, moon, and stars, and the weather.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun astronomy, meteorology The study of the theoretical effects of astronomical bodies and forces on the Earth’s atmosphere.