اللَّهُمَّ اسْقِنَا غَيْثاً مُغِيثاً مَرِيئاً مَرِيعاً، نَافِعاً غَيْرَ ضَارٍّ، عَاجِلاً غَيْرَ آجِلٍ

O Allah, shower upon us abundant rain, beneficial not harmful, swiftly and not delayed.

Allaahumma 'asqinaa ghaythan mugheethan maree'an maree'an, naafi'an ghayradhaarrin, 'aajilan ghayra 'aajilin.

Abu Dawud 1/303. See also Al-Albani SahihAbu Dawud 1/216.