Climate averages 1991–2020
Cilegon weather
in September.
A hot, moderately wet month: the 2nd 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 Cilegon: daytime highs average 30.1°C and nights cool to about 24.2°C. By daytime temperature it is the 2nd warmest of the 12 months.
Expect about 74 mm of rain on roughly 16 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 Serang (16 km away). In September its highs average 30.9°C, 0.8°C warmer than Cilegon, with 62 mm of rain.
Among the 200 cities listed in Indonesia, Cilegon ranks joint 101st of 200 for the warmest September highs and joint 102nd of 200 for the driest September (rainfall, lowest first). The mean September high of those 200 cities is 30.1°C; Cilegon is level with that mean.
From September to October, average highs stay level at 30.2°C, and monthly rainfall rises from 74 mm to 134 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
Cilegon climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 28.4°C24.3°C | 24.3°C | 286 | 28.7 | 12.412 h |
| February | 28.6°C24.4°C | 24.4°C | 264 | 26.4 | 12.312 h |
| March | 28.9°C24.7°C | 24.7°C | 251 | 28.0 | 12.112 h |
| April | 29.2°C24.8°C | 24.8°C | 218 | 26.5 | 12.012 h |
| May | 29.4°C24.8°C | 24.8°C | 165 | 23.8 | 11.812 h |
| June | 29.2°C24.4°C | 24.4°C | 120 | 20.1 | 11.812 h |
| July | 29.1°C23.9°C | 23.9°C | 94 | 18.1 | 11.812 h |
| August | 29.5°C23.9°C | 23.9°C | 70 | 16.9 | 11.912 h |
| September, selected | 30.1°C24.2°C | 24.2°C | 74 | 15.8 | 12.112 h |
| October | 30.2°C24.7°C | 24.7°C | 134 | 20.3 | 12.212 h |
| November | 29.3°C24.7°C | 24.7°C | 223 | 25.2 | 12.412 h |
| December | 28.3°C24.5°C | 24.5°C | 293 | 27.1 | 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
- Serang in SeptemberIndonesia · 16 kmHigh 30.9°C · Low 23.8°C · 62 mm rain
- Pandeglang in SeptemberIndonesia · 33 kmHigh 30.1°C · Low 22.1°C · 91 mm rain
- Kresek in SeptemberIndonesia · 38 kmHigh 31.4°C · Low 23.6°C · 70 mm rain
- Rangkasbitung in SeptemberIndonesia · 44 kmHigh 31.4°C · Low 22.7°C · 74 mm rain
- Pasarkemis in SeptemberIndonesia · 55 kmHigh 31.7°C · Low 22.8°C · 70 mm rain
- Curug in SeptemberIndonesia · 62 kmHigh 32.3°C · Low 22.6°C · 70 mm rain
- Teluknaga in SeptemberIndonesia · 65 kmHigh 32.0°C · Low 23.7°C · 38 mm rain
- Tangerang in SeptemberIndonesia · 66 kmHigh 31.9°C · Low 23.0°C · 57 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 Cilegon) is explained once on the Cilegon year overview and on the Sources, method and limits page.