Anas said the Prophet was not accustomed to raise his hands in any supplication he made except when praying for rain. He would then raise them high enough for the whiteness under his armpits to be visible.
‘Abdallah b. Zaid said God's Messenger took the people out to the place of prayer and prayed for rain. He led them in two rak'as in the course of which he recited from the Qur'an in a loud voice. He faced the qibla making supplication, raised his hands and turned round his cloak when he faced the qibla.