Sayyiduna Abdullah (may Allah be pleased with him) said that the Prophet (peace and blessings be upon him) said: "No year has more rain than another year, and whenever the south wind blows, such-and-such valley flows."
It has been narrated as marfu' with this chain, but the correct view is that it is mawquf (a statement of Abdullah).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة الاستسقاء / 6481