WEATHER · CLIMATE NORMALS · 1991–2020
Rio de Janeiro Climate — Averages by Month
What the weather in Rio de Janeiro, BRaverages across a standard 30-year period. Each month's figure is the 1991–2020 mean temperature and total rainfall from the ERA5 reanalysis — the long-run normal a place settles around, not a forecast for any particular day.
Month-by-month normals
| Month | Avg temperature | Avg rainfall |
|---|---|---|
| January | 26.6 °C | 175.4 mm · wettest |
| February | 26.9 °C · warmest | 122.6 mm |
| March | 26.1 °C | 152.0 mm |
| April | 24.8 °C | 94.8 mm |
| May | 22.6 °C | 81.8 mm |
| June | 21.7 °C | 51.8 mm |
| July | 21.1 °C · coldest | 55.0 mm |
| August | 21.5 °C | 45.6 mm |
| September | 22.2 °C | 80.5 mm |
| October | 23.3 °C | 97.7 mm |
| November | 24.1 °C | 145.0 mm |
| December | 25.6 °C | 156.9 mm |
How to read these numbers
These are reanalysis normals, not readings from a single weather station. They come from the ERA5 0.25° (~25 km) global reanalysis grid, sampled at the grid cell nearest Rio de Janeiro — centred at 23.00°S, 43.25°W. A reanalysis blends observations with a physics model onto an even grid, so a coastal or mountain city's cell can read a little cooler, warmer, wetter or drier than the city centre itself. The month-to-month shape — when it's hot, when it rains — is what these normals capture best.
“Normal” means the 1991–2020 average, the current World Meteorological Organization standard period. A normal is what a place tends toward over decades — any single day, month or year can and will depart from it.