The dry season runs from November through May, with the most reliable weather from January to April — flat seas, clear skies, and the best dive visibility. December and January can be windy on the open crossings to outer islands; March and April are hot and calm.
The wet season is June through October. Diving and snorkelling still happen most days, but typhoons can shut everything down for several days at a stretch, and visibility drops. Prices are noticeably lower in the wet months and the lakes and lagoons are emptier, so for some travellers the trade-off works.
Local festivals worth knowing about: the Pista del Imnasion in August commemorates the town's founding, and the patronal feast of San Agustín falls at the end of August.