´Mu’tamir narrated from his father, from Barakah, from Bashir bin Nahik, from Abu Hurairah:` “The Prophet (ﷺ) supplicated for rain (raising his hands) until I saw or one could see the whiteness of his armpits.”
Related hadith on this topic
Explanation & Benefits
Maulana Ataullah Sajid
Benefits and Issues:
➊ On the occasion of istisqa (prayer for rain), one should supplicate at length with deep humility and submissiveness.
➋ While supplicating during the prayer of istisqa, the hands should be raised higher than in ordinary circumstances.
Source: Commentary on Sunan Ibn Mājah by Mawlānā ‘Atā’ullāh Sājid, Page: 1271