Príncipe has two dry seasons: the main one runs from June to September (gravana), and a shorter dry period falls around January. These are the most comfortable months for hiking and beach-going, with less mud on the forest trails and calmer seas. The wet season (October to May, with a brief break) brings heavy rainfall, particularly in the south of the island where annual totals can exceed 7,000 mm — among the highest in the world.
Even in the wet season Príncipe has a certain appeal: the forest is at its most intensely green, waterfalls are at full force, and there are far fewer visitors. Birding is possible year-round. Sea turtles nest on the island's beaches between October and March; if you want to watch nesting or hatching, this is the time to come, with guided night excursions available.
The island has no major annual festivals, but July brings the national holiday of São Tomé and Príncipe Independence Day (12 July), which is celebrated with music and dancing in Santo António.