Petrópolis weather in January
In January, Petrópolis has daytime highs averaging 27 °C, nights around 19 °C, with 23 wet days. Figures are 1991–2020 climate normals.
- 26.8°C Average high
- 19.5°C Average low
- 23days Wet days
- 317mm Rainfall
- 13h Daylight
Daily temperatures through January
How January develops
Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.
| Days | Avg high | Avg low | Chance of rain |
|---|---|---|---|
| 1–10 January | 26.5 °C | 19.4 °C | 76 % |
| 11–20 January | 26.8 °C | 19.5 °C | 72 % |
| 21–31 January | 26.9 °C | 19.6 °C | 72 % |
What to expect
| Measure | Typical January | Share of the month |
|---|---|---|
| Days above 25 °C | 23 of 31 | 74 % |
| Days above 30 °C | 3.6 of 31 | 12 % |
| Days below 0 °C | 0 of 31 | 0 % |
| Days with more than 1 mm rain | 23 of 31 | 73 % |
Conditions in January
| Measure | Average |
|---|---|
| Mean temperature | 23 °C |
| Record high (1991–2020) | 34 °C |
| Record low (1991–2020) | 15 °C |
| Relative humidity | 81 % |
| Wind speed | 9.2 km/h |
| Cloud cover | 75 % |
January compared with the months around it
| Month | Avg high | Rainfall | Cloud |
|---|---|---|---|
| January | 26.8 °C | 317 mm | 75 % |
| February | 27.2 °C | 230 mm | 67 % |
| March | 25.7 °C | 255 mm | 69 % |
| November | 24.4 °C | 268 mm | 77 % |
| December | 25.9 °C | 299 mm | 76 % |
See all twelve months for Petrópolis
- January is the 2nd warmest month here.
- It is the 12th driest month of the year.
- It ranks 10th for least cloud cover.
- Days last about 13 hours from sunrise to sunset.
- It rains on 23 of 31 days — 73 % of the month.
- Nights are about 7.3 °C cooler than the middle of the day.
- The hottest January day on record since 1991 reached 34 °C, 6.7 °C above the usual daytime high.
QuestionsJanuary in Petrópolis, answered
How warm is Petrópolis in January?
Daily highs average 27 °C and nights fall to about 19 °C, a spread of 7.3 °C between afternoon and dawn. That makes January the 2nd warmest month of the year here.
Does it rain much in Petrópolis in January?
January averages 317 mm of rain, spread over about 23 of the 31 days — 73 % of the month. Cloud cover averages 75 % of the sky.
How long are the days in January?
Petrópolis averages 13 hours between sunrise and sunset in January. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.
Data sources and method
- ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
- Open-Meteo — Open-Meteo.com. CC BY 4.0
- NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
- GeoNames — GeoNames.org. CC BY 4.0
- Normal period
- 1991–2020
- Dataset version
- era5-1991-2020-scores1.1
- Last processed
Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. Full formulas are on the methodology page.
Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.