The best time to go to the Rosario Islands is during the dry season, which runs from December to April.During these months, you'll experience consistently sunny skies and calm seas, which are ideal for enjoying the islands' main attractions like snorkelling, diving, and boat trips between the islands. The water is often at its clearest, offering the best visibility for exploring the coral reefs.For those who prefer slightly fewer crowds, the shoulder months of May and November can also be a good option. While there might be occasional short showers, these usually pass quickly, and you can often find better deals on accommodation. However, the sea might be a little choppier compared to the peak dry season.Families travelling with children might find the dry season particularly appealing due to the predictable good weather, making it easier to plan activities and enjoy the beaches without interruption.