عَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ كَانَ إِذَا رَأَى الْمَطَرَ قَالَ: ((اللَّهُمَّ صَيِّبًا نَافِعًا))
Sayyidah Aisha (may Allah be pleased with her) says: Indeed, when the Messenger of Allah (peace and blessings be upon him) saw rain, he would say: "Allahumma sayyiban nafi'an." (O Allah! Make it a beneficial rain.)