Climate averages 1991–2020
Serang weather
in September.
A hot, moderately wet month: one of the warmest and the 2nd driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a hot month in Serang: daytime highs average 30.9°C and nights cool to about 23.8°C. By daytime temperature it is one of the warmest months of the year.
Expect about 62 mm of rain on roughly 14 days, which makes September a moderately wet month (the 2nd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 04 min on an average September day.
The nearest other city in this atlas is Cilegon (16 km away). In September its highs average 30.1°C, 0.8°C cooler than Serang, with 74 mm of rain.
Among the 200 cities listed in Indonesia, Serang ranks joint 74th of 200 for the warmest September highs and joint 87th of 200 for the driest September (rainfall, lowest first). The mean September high of those 200 cities is 30.1°C; Serang is 0.8°C warmer than that mean.
From September to October, average highs stay level at 30.9°C, and monthly rainfall rises from 62 mm to 119 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
Serang climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 28.6°C24.1°C | 24.1°C | 278 | 28.3 | 12.412 h |
| February | 28.8°C24.1°C | 24.1°C | 257 | 26.5 | 12.312 h |
| March | 29.2°C24.3°C | 24.3°C | 236 | 27.5 | 12.112 h |
| April | 29.5°C24.4°C | 24.4°C | 190 | 25.5 | 12.012 h |
| May | 29.7°C24.2°C | 24.2°C | 133 | 21.6 | 11.812 h |
| June | 29.6°C23.8°C | 23.8°C | 100 | 17.6 | 11.812 h |
| July | 29.5°C23.4°C | 23.4°C | 73 | 15.0 | 11.812 h |
| August | 30.1°C23.5°C | 23.5°C | 50 | 12.8 | 11.912 h |
| September, selected | 30.9°C23.8°C | 23.8°C | 62 | 14.2 | 12.112 h |
| October | 30.9°C24.3°C | 24.3°C | 119 | 20.7 | 12.212 h |
| November | 29.8°C24.4°C | 24.4°C | 192 | 25.8 | 12.412 h |
| December | 28.7°C24.2°C | 24.2°C | 256 | 26.3 | 12.512 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
- Cilegon in SeptemberIndonesia · 16 kmHigh 30.1°C · Low 24.2°C · 74 mm rain
- Pandeglang in SeptemberIndonesia · 22 kmHigh 30.1°C · Low 22.1°C · 91 mm rain
- Kresek in SeptemberIndonesia · 25 kmHigh 31.4°C · Low 23.6°C · 70 mm rain
- Rangkasbitung in SeptemberIndonesia · 29 kmHigh 31.4°C · Low 22.7°C · 74 mm rain
- Pasarkemis in SeptemberIndonesia · 42 kmHigh 31.7°C · Low 22.8°C · 70 mm rain
- Curug in SeptemberIndonesia · 48 kmHigh 32.3°C · Low 22.6°C · 70 mm rain
- Tangerang in SeptemberIndonesia · 53 kmHigh 31.9°C · Low 23.0°C · 57 mm rain
- Teluknaga in SeptemberIndonesia · 54 kmHigh 32.0°C · Low 23.7°C · 38 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 Serang) is explained once on the Serang year overview and on the Sources, method and limits page.