At the end of August, did beginning of autumn withdraw its summer mat at night 15?

At the end of August, the summer sleeping mat was removed at the temperature of beginning of autumn 15. Because the temperature dropped at night and in the morning and evening after beginning of autumn at the end of August, it is best to remove the summer sleeping mat, otherwise it may lead to arthritis, disc herniation and other diseases. So at the end of August, beginning of autumn took back its summer sleeping mat at night 15 degrees.