The Esteemed and Noble Shaykh Ṣāliḥ Bin Fawzān Al-Fawzān حفظه اللهwho is a member of the Council of Major Scholars and a member of the Permanent Committee for issuing Islāmic Rulings for the General masses of Muslims, pointed out (the following):
When there is an abundant amount of rainfall and it is feared some harm (due to the tumultuous rainfall) the Muslim should supplicate to his Lord and thus say,
اللهم حولينا ولا علينا، اللهم على الضراب والآكام وبطون الأودية ومنابت الشجر
O Allah (let it rain) around us and not upon us; O Allah let it rain upon the plateaus/hills, mountains, center of the valleys and on the groves of tress (or the places where trees grow). [Bukhaari & Muslim]
Then the his eminence turned his attention to the Prophet’s ﷺ guidance as relates to (regular) rainfall (where) he would say,
مطرنا بفضل الله وبرحمته، اللهم صيبا نافعا
Rain is upon us by the bounty and mercy of Allah; O Allah make these rain clouds beneficial. [Bukhaari & Muslim]
Then his eminence supplicated to (Allah) the Protector عز وجل that He benefit the country and servants with the rain and (and that He) makes it (for them) a mercy and blessing which quenches their thirst.