Granite peaks dropping straight into the Atlantic, with a summer that is as humid as it is famous. Rio de janeiro barely has a temperature season: daytime highs move only about 5 °C across the whole year, from 24 °C in June to 29 °C in February. What changes instead is rain.
Measured against a beach trip, the conditions hold up June to August. July is the most consistent single month: highs near 24 °C, nights around 17 °C, and roughly 55 mm of rain across the month.
The binding constraint here is rainfall — that is what rules months out, not any composite judgement. Rainfall is sharply seasonal: December averages 242 mm against 55 mm in July, so the wet season is the real planning constraint rather than heat or cold. January is the weakest month on these criteria.
Month by month
| Month | High °C | Low °C | Precip mm | Wet days |
|---|---|---|---|---|
| January | 29 | 23 | 238 | 19.0 |
| February | 29 | 23 | 200 | 16.2 |
| March | 28 | 23 | 187 | 18.7 |
| April | 26 | 21 | 136 | 15.1 |
| May | 25 | 19 | 88 | 13.0 |
| June | 24 | 18 | 55 | 8.8 |
| July | 24 | 17 | 55 | 8.4 |
| August | 24 | 18 | 65 | 8.7 |
| September | 25 | 19 | 83 | 11.5 |
| October | 26 | 20 | 130 | 15.5 |
| November | 26 | 21 | 185 | 18.4 |
| December | 27 | 22 | 242 | 20.1 |
Ticked rows are months where every hard requirement for a beach trip is met across at least half the month.
Open Rio de Janeiro on the map →Nearby regions
Figures are 30-year climatology sampled at Rio de Janeiro, Buzios, Paraty and Niteroi, averaged across those locations, from ERA5-Land reanalysis fitted with a harmonic seasonal cycle and a trend term, evaluated for 2026. Sampling named towns rather than averaging the whole region avoids blending valley and mountain conditions into a figure true of neither. Cells are about 0.08° wide, from ERA5-Land's 0.1° grid, which is itself driven by a 0.25° (~28 km) atmospheric reanalysis — so individual valleys, sheltered bays and single summits are not resolved. In steep terrain read these as conditions for the wider area rather than for one village. They describe typical conditions, not a forecast. Read how the climatology is built.