Pre-Islamic Arabia ran a weather calendar off the lunar mansions: each one's dawn rising was tied to a season, a rain, a wind or a date harvest.

The anwā' system is the desert equivalent of a farmer's almanac, and it is one of the oldest bodies of practical star knowledge in Arabic. The book titles survive — Ibn Qutayba wrote one in the ninth century — and it is meteorology rather than astrology: the star does not cause the rain, it tells you what time of year it is.