Planning for the weather is a good way to make your trip to Antofagasta relaxing and enjoyable, especially when you’re splurging. The hottest months are usually February and January with an average temp of 68°F, while the coldest months are July and August with an average of 59°F. From January through March, the daytime average is 75°F and the nighttime average is 64°F. Between April and June, temperatures average 70°F during the day and 56°F at night. July through September averages 65°F during the day and 54°F at night. In October-December, the average temperature is 71°F during the day and 56°F at night.