"The Messenger of Allah went out with the people to seek rain. So he led them in prayer for two Rak'ah, reciting aloud in them, turning his upper wrap around, raising his hands, requesting rain, and facing the Qiblah."  

أَنَّ رَسُولَ اللَّهِ ﷺ خَرَجَ بِالنَّاسِ يَسْتَسْقِي فَصَلَّى بِهِمْ رَكْعَتَيْنِ جَهَرَ بِالْقِرَاءَةِ فِيهِمَا وَحَوَّلَ رِدَاءَهُ وَرَفَعَ يَدَيْهِ وَاسْتَسْقَى وَاسْتَقْبَلَ الْقِبْلَةَ قَالَ وَفِي الْبَابِ عَنِ ابْنِ عَبَّاسٍ وَأَبِي هُرَيْرَةَ وَأَنَسٍ وَآبِي اللَّحْمِ  

he saw the Messenger of Allah at Ahjar Az-Zait, supplicating for rain, and he was raising his hands in supplication.  

أَنَّهُ رَأَى رَسُولَ اللَّهِ ﷺ عِنْدَ أَحْجَارِ الزَّيْتِ يَسْتَسْقِي وَهُوَ مُقْنِعٌ بِكَفَّيْهِ يَدْعُو  

"Al-Walid bin Uqbah, the governor of Al-Madinah, sent me to ask Ibn Abbas about how the Messenger of Allah would perform Salat Al-Istisqa. I came to him and he said: 'The Messenger of Allah would go out in modest dress, humbly, imploring, until he reached the Musalla. He would not give this Khutbah of yours, rather, he would continue supplication and imploring saying the Takbir, and pray two Rak'ah, just as he would pray for the Eid.'"  

عَنِ اسْتِسْقَاءِ رَسُولِ اللَّهِ ﷺ فَأَتَيْتُهُ فَقَالَ إِنَّ رَسُولَ اللَّهِ ﷺ خَرَجَ مُتَبَذِّلاً مُتَوَاضِعًا مُتَضَرِّعًا حَتَّى أَتَى الْمُصَلَّى فَلَمْ يَخْطُبْ خُطْبَتَكُمْ هَذِهِ وَلَكِنْ لَمْ يَزَلْ فِي الدُّعَاءِ وَالتَّضَرُّعِ وَالتَّكْبِيرِ وَصَلَّى رَكْعَتَيْنِ كَمَا كَانَ يُصَلِّي فِي الْعِيدِ  

and he mentioned a similar narration and added: "with humility" to it.  

عَنْ أَبِيهِ فَذَكَرَ نَحْوَهُ وَزَادَ فِيهِ مُتَخَشِّعًا