Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: The Prophet (peace and blessings be upon him) came out to us while a cloud was overshadowing us, and we were hoping for something from it (that it would bring rain). The Prophet (peace and blessings be upon him) said: "The angel who is driving it, (the narrator is unsure; perhaps the words are:) who is driving this cloud, came to me, greeted me with salam, and informed me that he is driving it to such-and-such a valley."
Al-Bazzar recorded it, and its narrators are thiqat (trustworthy).