On clear nights, there is less friction against the wings which makes for obstruction-free sailing across the sky. Less air traffic also means smoother cruising, since most pilots can sit back and not worry about the aircraft in their path.
Is it better to take a flight in the morning or at night?
The early bird may be known for catching the worm, but it also catches the best flights. In fact, people who get the first flight in the morning can usually expect a smoother trip, friendlier staff, a cleaner plane and, often, a cheaper ticket.
What is the best time to go on a flight?
Flying on weekdays, mainly Tuesdays and Wednesdays, results in lower airfare than on weekends. Additionally, early-morning and late-night flights are often cheaper than peak-time flights. Be open to traveling on different days and at varying times to have a better chance of finding an affordable flight.