It is narrated from Sayyiduna Jabir bin Abdullah (may Allah be pleased with them both) that weeping people came to the Messenger of Allah (peace and blessings be upon him) (and spoke to him), so he (peace and blessings be upon him) supplicated: "O Allah, grant us rain that is helpful, quenching and bringing greenery, swift and not delayed, beneficial and not harmful." Then the clouds spread over them like a covering plate.
Abu al-Abbas narrates in a hadith that people of the tribe of Hawazin came to the Prophet (peace and blessings be upon him) for supplication, and he (peace and blessings be upon him) said: "Say: 'Allahummasqina' (O Allah, give us water to drink)."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة الاستسقاء / 6437