Water temperature in Brazil

Brazil's Atlantic coast, north to south

Brazil has a very long Atlantic coastline. In the tropical northeast, the sea is warm all year and the seasons make little difference. Further south the contrast grows, and in the southern states the water can be quite fresh in winter. As Brazil lies in the southern hemisphere, the main beach season runs from December to March. During the rainy season, river mouths can carry plenty of fresh water and sediment to the coast.

All 18 sites rely on modelled values. Temperatures come from the Open-Meteo marine model, which calculates sea surface temperature just offshore, and the app labels them as model values. They reflect conditions along a stretch of coast well but can differ in bays or near river mouths. Measured readings from Brazilian stations are not yet part of this dataset. Beaches are officially tested independently of these temperature figures.

In many states, environmental agencies regularly assess whether beaches are suitable for bathing and publish where swimming is recommended. After heavy rain, water quality near storm drains and river mouths often deteriorates, and such spots are best avoided for a while. On open Atlantic beaches, surf and rip currents can be powerful. Lifeguards mark dangerous stretches with flags, and their advice should be followed.