Due to multiple factors, expect to potentially pay more when booking in December. For low rates, February can be a great choice for travel to Ciudad Juárez. Flights to Ciudad Juárez from Santa Ana in February are about $356 on average during February, but can be found for as low as $194.
Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Santa Ana to Ciudad Juárez as you normally would.