Rio Seco, Ecuador offers 1 beach perfect for sunbathing, surfing, swimming, and more. Rio Seco, Manabi, Ecuador, is known for its proximity to the Machalilla National Park and the beautiful beaches of Puerto Lopez. The best time to travel to Rio Seco, Ecuador, is from June to September, with average air temperatures around 70-80°F (21-27°C) and water temperatures near 75°F (24°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!