Abu Dawud Book 2, Hadith Number 1169.
Narated By ‘Aisha, Ummul Mu’minin : The people complained to the Apostle of Allah (PBUH) of the lack of rain, so he gave an order for a pulpit. It was then set up for him in the place of prayer. He fixed a day for the people on which they should come out.
‘Aisha said: The Apostle of Allah (PBUH), when the rim of the sun appeared, sat down on the pulpit, and having pronounced the greatness of Allah and expressed His praise, he said: You have complained of drought in your homes, and of the delay in receiving rain at the beginning of its season. Allah has ordered you to supplicate Him has and promised that He will answer your prayer.
Then he said: Praise be to Allah, the Lord of the Universe, the Compassionate, the Merciful, the Master of the Day of Judgment. There is no god but Allah Who does what He wishes. O Allah, Thou art Allah, there is no deity but Thou, the Rich, while we are the poor. Send down the rain upon us and make what Thou sendest down a strength and satisfaction for a time.
He then raised his hands, and kept raising them till the whiteness under his armpits was visible. He then turned his back to the people and inverted or turned round his cloak while keeping his hands aloft. He then faced the people, descended and prayed two rak’ahs.
Allah then produced a cloud, and the storm of thunder and lightning came on. Then the rain fell by Allah’s permission, and before he reached his mosque streams were flowing. When he saw the speed with which the people were seeking shelter, he (PBUH) laughed till his back teeth were visible.
Then he said: I testify that Allah is Omnipotent and that I am Allah’s servant and apostle.