Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Savannah to Tokyo Narita Airport as you normally would.
Due to multiple factors, expect to potentially pay more when booking in July. For low rates, February can be a great choice for travel to Tokyo Narita Airport. Flights to Tokyo Narita Airport from Savannah in February are about $1,333 on average during February, but can be found for as low as $981.