Dua when it rains

Invocation for when it rains
 

اللّهُمَّ صَيِّـباً نافِـعاً

172. Allaahumma sayyiban naafi'an

O Allah , (bring) beneficial rain clouds.

Reference: Al-Bukhari, cf. Al-Asqalani, Fathul-Bari 2/518