Sahih al-Bukhari 1025Book 15, Hadith 20
حَدَّثَنَا آدَمُ، قَالَ حَدَّثَنَا ابْنُ أَبِي ذِئْبٍ، عَنِ الزُّهْرِيِّ، عَنْ عَبَّادِ بْنِ تَمِيمٍ، عَنْ عَمِّهِ، قَالَ رَأَيْتُ النَّبِيَّ صلى الله عليه وسلم يَوْمَ خَرَجَ يَسْتَسْقِي قَالَ فَحَوَّلَ إِلَى النَّاسِ ظَهْرَهُ، وَاسْتَقْبَلَ الْقِبْلَةَ يَدْعُو، ثُمَّ حَوَّلَ رِدَاءَهُ، ثُمَّ صَلَّى لَنَا رَكْعَتَيْنِ جَهَرَ فِيهِمَا بِالْقِرَاءَةِ.
"I saw the Prophet (ﷺ) on the day when he went out to offer the Istisqa' prayer. He turned his back towards the people and faced the Qibla and asked Allah for rain. Then he turned his cloak inside out and led us in a two rak`at prayer and recited the Qur'an aloud in them."