Should recitation in Salat al-Istisqa be audible (Jahri)?
Chapter on the Prayer for Rain (Istisqa)
Al-Mughni
Book of the Eclipse Prayers (Solar and Lunar)
Primary text
It is Sunnah to recite audibly (Jahri) in the prayer, as 'Abdullah ibn Zayd narrated that the Prophet, peace be upon him, turned his cloak, prayed two rak'ahs, and recited audibly in them. It is excellent if he recites Surah Al-A'la in the first rak'ah and Surah Al-Ghashiyah in the second, following the precedent of the Eid prayer, based on the narration of Ibn 'Abbas.
Supporting text
Anas narrated that the Prophet, peace be upon him, led them in two rak'ahs, reciting audibly, specifically reciting Surah Al-A'la in the first rak'ah after Al-Fatiha, and Surah Al-Ghashiyah in the second rak'ah after Al-Fatiha, during the Eid and Istisqa prayers.