This densely populated region has a true tropical seasonality. Summer brings torrential, often catastrophic, rainfall (e.g., flooding in São Paulo). Winter (June-August) is mild (15-20°C) and dry, with the occasional passage of friagens (cold fronts from the South) dropping temperatures suddenly.
The seasons are defined by flood and ebb. The Summer (wet) transforms the Pantanal into a vast flooded plain, while Winter (dry) is extremely dry, with relative humidity dropping below 20%. The Brazilian "winter" here is a desert-like season.
| City | Summer (Dec-Feb) | Winter (Jun-Aug) | | :--- | :--- | :--- | | Manaus (Amazon) | Very hot, heavy rain | Warm, less rain | | Salvador (NE Coast) | Hot, humid | Warm, pleasant | | Brasília (Central) | Rainy, thunderstorms | Dry, cool nights | | São Paulo (SE) | Rainy, humid (22-28°C) | Dry, mild (12-20°C) | | Porto Alegre (South) | Hot, storms (22-32°C) | Cold, foggy (8-18°C) |
The only region with well-defined thermal seasons. Summer is hot (above 30°C), Autumn features foliage change (rare in Brazil), Winter brings frost, fog, and occasional snowfall (e.g., in São Joaquim). Spring is marked by severe thunderstorms and hail.
Unlike countries in the Northern Hemisphere, Brazil’s seasons are reversed: Summer occurs from December to March, and Winter from June to September. However, due to Brazil’s proximity to the Equator (92% of the country lies within the intertropical zone), seasonal temperature variation is often less significant than seasonal precipitation variation. This paper argues that rainfall seasonality , rather than thermal seasonality, is the primary driver of ecological, agricultural, and social rhythms in most of Brazil.
The Seasons of Brazil: A Study of Climatic Regionality and Meteorological Dynamics
Brazil is a country of continental dimensions, featuring a wide range of climatic zones that defy the simplistic binary of “hot” or “cold.” This paper analyzes the seasonal patterns of Brazil, focusing on the meteorological definition of seasons (Spring, Summer, Autumn, Winter) relative to the country’s position in the Southern Hemisphere. It explores how seasonal manifestations vary across five distinct climatic regions: the Equatorial North, the Semi-arid Northeast, the Tropical Central, the High-Altitude Southeast, and the Subtropical South. The paper concludes that while Brazil experiences four theoretical seasons, their practical impacts—especially temperature, precipitation, and extreme weather events—are dictated more by regional geography and the South Atlantic Convergence Zone (SACZ) than by calendar dates.