I know Joshua Tree in August is 100°F during the day but the Perseid Meteor Shower is August 12-13 from 10pm to sunrise. At night, the temperature is a comfortable 70-80°F. It’s a unique opportunity to photograph the meteor shower with the Milky Way. The meteor shower is Saturday night August 12 until Sunday morning. There’s no moon that night and the Milky Way will be visible all night. Best viewing is in Joshua Tree National Park starting at 10pm until 5am the next morning.
Perseid Meteor Shower Joshua Tree Instagram Post