Sunan Abu Dawud
1057
Sahih+3

Narrated Usamah ibn Umayr al-Huzali: The rain was falling on the day when the Battle of Hunayn took place. The Prophet (ﷺ), therefore, commanded that the people should offer their prayer in their camps

SahihAl-Albani
SahihMuhammad Muhyi Al-Din Abdul Hamid