Agua, El Salvador offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Agua, La Union, El Salvador, is known for its proximity to the Gulf of Fonseca and the scenic Conchagua Volcano. The best time to travel to Agua, El Salvador, is from November to April, with average air temperatures around 75-85°F (24-29°C) and water temperatures near 82°F (28°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!