The Prophet (peace be upon him) was not accustomed to raise his hands in any supplication he made except when praying for rain. He would then raise them high enough so much so that the whiteness of his armpits was visible. (Using translation from Abū Dāʾūd 1170)
أَنَّ النَّبِيَّ ﷺ كَانَ لَا يَرْفَعُ يَدَيْهِ فِي شَيْءٍ مِنَ الدُّعَاءِ إِلَّا عِنْدَ الِاسْتِسْقَاءِ حَتَّى يُرَى بَيَاضُ إِبْطَيْهِ