When is the best time to visit Brazil? It is good to visit Brazil year round. The climate varies from region to region. Brazil has a tropical climate and lies in the Southern Hemisphere, so its seasons are the exact opposite to the Northern Hemisphere:
Summer – mid December to mid March: It is usually very humid and hot
Autumn – mid March to mid June: there is less rain, but it depends of the region
Winter – mid June to mid September: very little rain, apart from the beaches of the North-East, Roraima and Pico da Neblina, it is chilly at night in the South
Spring – mid September to mid December: it varies from region to region, but there is less rain
Costa Verde: Rio de Janeiro and Sao Paulo have hot and humid summers with a temperature of 38°C and 98% humidity. The winters are quite mild, with night temperatures dropping to 19°C, and daytime temperatures climbing to 30°C. Note that most houses and apartments are built to reduce the heat, and many restaurants and stores lack windows or doors, so it can feel chilly in the evening. São Paulo can sometimes get chillier than Rio, with daytime lows in June to September reaching 12°C. In Petrópolis and the historic towns of Minas Gerais it often gets cold enough to see your breath (5°C) in the fall and winter.
North-East & Fernando de Noronha: In the North-East it is warm year-round with a pleasant ocean breeze. Temperatures vary between 25 and 35 °C. Short showers cool things down during winter months (June-July). Enjoy the beaches of Bahia, Pernambuco, Alagoas, Rio Grande do Norte.
Lencois Maranhenses & Jericoacoara: The park of Lençóis Maranhenses is good to visit after the rainy season, when the lagoons are full of water. This is the case from mid May till the beginning of October. Jericoacoara and Ceara one can visit year round.
Amazon: In the Amazon it is hot and humid year-round, with temperatures hovering around 35-39 °C. The dry season lasts from June to December, when it is hot and sunny. As the rivers recedes, beaches and islands re-appear. The wet season typically runs from December to May. The humidity is higher, building up over the course of the day to produce a heavy downfall almost every afternoon. Even then, mornings and early afternoons can be clear and sunny. The best time to visit the Amazon is between July to October, when it is dry. There are some advantages of seeing the Amazon at high water, when the forest is flooded and one can navigate between the branches of the trees in a canoe – this is possible during the rainy season. There is also a chance to spot the jaguar climbing the trees during the rainy season.
Pantanal: The Pantanal is very hot during the rainy season (December to March), with temperatures reaching 40°C. The driest time of the year is May through to October. Things cool down considerably, although night time temperatures will seldom drop below 20°C. The best time to see animals, is during the dry season from April/ May to October.
South: Here things get colder in the winter, from June to September, but it is a good time to visit Aparados da Serra because there won’t be so much fog and one can enjoy the views. In Florianópolis, many restaurants and even some hotels shut down for the winter season and there is a possibility of snow in the highlands of Rio Grande do Sul and Santa Catarina. The dry season in the south runs from March to November, whereas December to February are wet and rainy. Best time to see whales in Praia de Rosa is from July to October.
Very South: Iguazu Falls is good to visit at anytime. The falls are at the fullest in the rainy season, but usually at that time most of the trails are closed. This is the case from December to February, which is also a busy time with lots of crowds. For clear skies and hiking the trails is best to go during the dry season, so from June onwards. There is never a safe bet.
Chapadas & Jalapao: Chapada Diamantina, Chapda dos Veadeiros, Chapada dos Guimaraes and Chapada das Mesas, as well as Jalapao, lie in the cerrado area, which is inland, far away from the beaches. It is good to visit them year round, but the best time is from April to October, when it is sunny and hot. For waterfalls it is good to visit during the rainy season, from November to March, but one needs to be cautious of walking on slippery trails.