Is it permissible for a man to go to the mosque to pray while leaving his wife and daughters in the car, whether he is traveling or a resident?

There is no harm for a man to leave his wife and daughters in the car while he goes to fulfill a need such as prayer or the like, whether traveling or not, as long as the place is safe. If there is a designated area for women to pray in the mosque, then it is preferable for the wife and discerning daughters to pray in congregation at the mosque if they fear missing the beginning of the prayer time.