Climate averages 1991–2020
Barra do Piraí weather
in September.
A warm, moderately wet month: the 8th warmest and the 5th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Barra do Piraí: daytime highs average 26.4°C and nights cool to about 16.9°C. By daytime temperature it is the 8th warmest of the 12 months.
Expect about 66 mm of rain on roughly 10 days, which makes September a moderately wet month (the 5th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 11 h 57 min on an average September day.
The nearest other city in this atlas is Japeri (26 km away). In September its highs average 28.0°C, 1.6°C warmer than Barra do Piraí, with 79 mm of rain.
Among the 448 cities listed in Brazil, Barra do Piraí ranks joint 268th of 448 for the warmest September highs and joint 237th of 448 for the driest September (rainfall, lowest first). The mean September high of those 448 cities is 27.5°C; Barra do Piraí is 1.1°C cooler than that mean.
From September to October, average highs rise by 0.9°C to 27.3°C, and monthly rainfall rises from 66 mm to 112 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Barra do Piraí climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 29.4°C21.2°C | 21.2°C | 282 | 22.0 | 13.313 h |
| February | 30.0°C21.3°C | 21.3°C | 202 | 17.7 | 12.913 h |
| March | 28.4°C20.6°C | 20.6°C | 195 | 20.5 | 12.212 h |
| April | 26.8°C19.0°C | 19.0°C | 89 | 12.3 | 11.612 h |
| May | 24.5°C16.3°C | 16.3°C | 53 | 9.1 | 11.111 h |
| June | 24.2°C14.9°C | 14.9°C | 28 | 5.4 | 10.811 h |
| July | 24.0°C14.4°C | 14.4°C | 28 | 5.4 | 10.911 h |
| August | 25.3°C15.1°C | 15.1°C | 27 | 5.4 | 11.311 h |
| September, selected | 26.4°C16.9°C | 16.9°C | 66 | 9.9 | 11.912 h |
| October | 27.3°C18.4°C | 18.4°C | 112 | 13.9 | 12.613 h |
| November | 27.0°C19.2°C | 19.2°C | 202 | 19.1 | 13.213 h |
| December | 28.5°C20.5°C | 20.5°C | 248 | 22.1 | 13.513 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Japeri in SeptemberBrazil · 26 kmHigh 28.0°C · Low 18.5°C · 79 mm rain
- Valença (Rio de Janeiro), Brazil in SeptemberBrazil · 28 kmHigh 25.4°C · Low 15.6°C · 76 mm rain
- Volta Redonda in SeptemberBrazil · 29 kmHigh 26.3°C · Low 15.9°C · 63 mm rain
- Seropédica in SeptemberBrazil · 33 kmHigh 27.2°C · Low 17.8°C · 79 mm rain
- Barra Mansa in SeptemberBrazil · 36 kmHigh 26.2°C · Low 15.9°C · 69 mm rain
- Queimados in SeptemberBrazil · 39 kmHigh 27.2°C · Low 17.8°C · 66 mm rain
- Itaguaí in SeptemberBrazil · 43 kmHigh 26.4°C · Low 18.6°C · 79 mm rain
- Nova Iguaçu in SeptemberBrazil · 50 kmHigh 27.4°C · Low 18.1°C · 66 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Barra do Piraí) is explained once on the Barra do Piraí year overview and on the Sources, method and limits page.