Sahih al-Bukhari 1026
صحيح البخاري#1026SahihNarrated `Abbad bin Tamim from his uncle who said:"The Prophet (ﷺ) invoked Allah for rain and offered a two rak`at prayer and he put his cloak inside out
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 15:21