Ilhabela has a relatively mild tropical climate. Summer can get hot and humid, 30ºC is not uncommon, while winter is very dry and sunny. Usually, the rain falls in the summer months (December until March). About 85% of its territory (the average temperature is 73º F) is part of the State Park of Ilhabela, assuring the preservation of the last remaining and one of the most beautiful reservation of the Atlantic Forest (declared Biosphere Sanctuary by the UNESCO).
The climate is tropical humid coastal, or tropical Atlantic, predominantly hot and humid, with average annual temperature of 24.8°C (75º F). The hottest month is usually February, with an average temperature of 28.2° C (85º F), and the coldest is usually July with average of 20.7 ° C (20º F). The highest concentration of rainfall tends to be in the summer months , which is also when the island is more crowded with tourists (especially for the Carnival and New Year). The autumn days can provide beautiful views with sun and blue sky, and more tranquility and more attractive prices for those seeking relaxation by the sea.