Seasons

Seasons below the Equator are the reverse of those north of it: Summer in Brazil runs from December to March and winter from June to September. The rainy season occurs during the summer months, but in most parts of Brazil is rarely a nuisance. Showers can be torrential but usually last no more than an hour or two, after which the sun reappears. The areas of the country with pronounced rainy seasons are the Amazon and the Pantanal Wetlands. In these regions, the rainy season runs roughly November to May and is marked by heavy downpours that usually occur twice a day.

Rio de Janeiro is on the Tropic of Capricorn, and its climate is just that -- tropical. Summers are hot and humid, with temperatures rising as high as 105°F (40°C), although the average ranges between 84°F and 95°F (29°C-35°C). In winter, temperatures stay in the 70s (20s°C), occasionally dipping into the high 60s (15°C-20°C). The same pattern holds true for all of the Brazilian coastline north of Rio, although in general temperatures are slightly higher year-round in Salvador and the coastal cities of the northeast. In the Amazon region where the equator crosses the country, temperatures in the high 80s to 90s (30s C) are common throughout the year. In the south, São Paulo, and parts of Minas Gerais, winter temperatures can fall to the low 40s (5°C-8°C). In the southern states of Santa Catarina and Rio Grande do Sul, snowfalls occur in winter, although they're seldom more than dusting's.

Weather Chart
 

The following are the normal daily temperature ranges for Rio:

January 84-69°F (29-21°C); February 85-73°F (29-23°C); March 83-72°F (28-22°C);

April 80-69°F (27-21°C); May 77-66°F (25-19°C); June 76-64°F (24-18°C);

July 75-64°F (24-18°C); August 76-64°F (24-18°C); September 75-66°F (24-19°C);

October 77-63°F (25-17°C); November 79-68°F (26-20°C); December 82-71°F (28-22°C).