Abd al-Rahman bin Mikhraq narrates from Sayyiduna Abu Dharr (may Allah be pleased with him), and he traces it back to the Prophet (peace and blessings be upon him), that he (peace and blessings be upon him) said: "Indeed Allah Almighty created a wind in Paradise seven years after the other wind; behind it is a closed door, and the wind that reaches you comes through the gaps of that door. If that door were opened, whatever is between the sky and the earth would be overturned. With Allah Almighty it is (called) al-Azyab, and with you it is the south wind."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة الاستسقاء / 6489