Climate averages 1991–2020
São Gonçalo 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 São Gonçalo: daytime highs average 26.3°C and nights cool to about 18.1°C. By daytime temperature it is the 8th warmest of the 12 months.
Expect about 85 mm of rain on roughly 11 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 Rio de Janeiro (16 km away). In September its highs average 26.8°C, 0.6°C warmer than São Gonçalo, with 75 mm of rain.
Among the 448 cities listed in Brazil, São Gonçalo ranks joint 272nd of 448 for the warmest September highs and joint 309th of 448 for the driest September (rainfall, lowest first). The mean September high of those 448 cities is 27.5°C; São Gonçalo is 1.3°C cooler than that mean.
From September to October, average highs rise by 1.1°C to 27.4°C, and monthly rainfall rises from 85 mm to 114 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
São Gonçalo climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 30.1°C23.0°C | 23.0°C | 244 | 20.4 | 13.413 h |
| February | 30.5°C23.1°C | 23.1°C | 183 | 17.0 | 12.913 h |
| March | 29.0°C22.4°C | 22.4°C | 205 | 19.6 | 12.212 h |
| April | 27.3°C20.8°C | 20.8°C | 101 | 13.2 | 11.612 h |
| May | 25.0°C18.3°C | 18.3°C | 75 | 10.5 | 11.011 h |
| June | 24.6°C17.1°C | 17.1°C | 48 | 7.0 | 10.811 h |
| July | 24.3°C16.4°C | 16.4°C | 49 | 7.2 | 10.911 h |
| August | 25.3°C16.8°C | 16.8°C | 44 | 7.3 | 11.311 h |
| September, selected | 26.3°C18.1°C | 18.1°C | 85 | 10.7 | 11.912 h |
| October | 27.4°C19.6°C | 19.6°C | 114 | 13.3 | 12.613 h |
| November | 27.4°C20.5°C | 20.5°C | 204 | 18.0 | 13.213 h |
| December | 29.1°C22.1°C | 22.1°C | 229 | 19.9 | 13.514 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
- Rio de Janeiro in SeptemberBrazil · 16 kmHigh 26.8°C · Low 18.6°C · 75 mm rain
- Magé in SeptemberBrazil · 19 kmHigh 26.3°C · Low 17.6°C · 85 mm rain
- Itaboraí in SeptemberBrazil · 22 kmHigh 25.9°C · Low 17.4°C · 82 mm rain
- Maricá in SeptemberBrazil · 26 kmHigh 26.0°C · Low 19.2°C · 61 mm rain
- Duque de Caxias in SeptemberBrazil · 27 kmHigh 27.1°C · Low 18.2°C · 86 mm rain
- Belford Roxo in SeptemberBrazil · 36 kmHigh 27.3°C · Low 18.3°C · 66 mm rain
- Barra da Tijuca in SeptemberBrazil · 37 kmHigh 27.5°C · Low 19.0°C · 75 mm rain
- Petrópolis in SeptemberBrazil · 38 kmHigh 23.8°C · Low 15.1°C · 88 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 São Gonçalo) is explained once on the São Gonçalo year overview and on the Sources, method and limits page.
Magé lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.