Sahih al-Bukhari 1028
صحيح البخاري#1028SahihNarrated `Abdullah bin Zaid Al-Ansari:The Prophet (ﷺ) went out towards the Musalla in order to offer the Istisqa' prayer and when he intended to invoke (Allah) or started invoking, he faced the Qibla and turned 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: 15:23