Playa Copalito, Mexico offers 1 beach perfect for sunbathing, surfing, swimming, and more. Playa Copalito, Oaxaca, Mexico, is known for its beautiful beaches and proximity to the renowned Huatulco Bays. The best time to travel to Playa Copalito, Mexico, is between November and April, when the average air temperature is around 75-85°F (24-29°C) and the water temperature is approximately 78-82°F (26-28°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!