Climate averages 1991–2020
Bontang weather
in September.
A hot, 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 Bontang: daytime highs average 29.6°C and nights cool to about 24.4°C. By daytime temperature it is one of the warmest months of the year.
Expect about 130 mm of rain on roughly 20 days, which makes September a wet month (the 2nd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 07 min on an average September day.
The nearest other city in this atlas is Samarinda (79 km away). In September its highs average 30.6°C, 1.0°C warmer than Bontang, with 173 mm of rain.
Among the 200 cities listed in Indonesia, Bontang ranks joint 120th of 200 for the warmest September highs and joint 145th of 200 for the driest September (rainfall, lowest first). The mean September high of those 200 cities is 30.1°C; Bontang is 0.5°C cooler than that mean.
From September to October, average highs stay level at 29.6°C, and monthly rainfall rises from 130 mm to 176 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
Bontang climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 28.9°C24.1°C | 24.1°C | 205 | 25.2 | 12.112 h |
| February | 29.1°C24.2°C | 24.2°C | 164 | 22.1 | 12.112 h |
| March | 29.3°C24.3°C | 24.3°C | 206 | 25.3 | 12.112 h |
| April | 29.4°C24.4°C | 24.4°C | 214 | 26.5 | 12.112 h |
| May | 29.3°C24.6°C | 24.6°C | 197 | 27.0 | 12.112 h |
| June | 29.0°C24.4°C | 24.4°C | 177 | 24.8 | 12.112 h |
| July | 28.9°C24.2°C | 24.2°C | 150 | 22.3 | 12.112 h |
| August | 29.2°C24.3°C | 24.3°C | 124 | 19.9 | 12.112 h |
| September, selected | 29.6°C24.4°C | 24.4°C | 130 | 20.4 | 12.112 h |
| October | 29.6°C24.4°C | 24.4°C | 176 | 25.3 | 12.112 h |
| November | 29.2°C24.2°C | 24.2°C | 220 | 28.3 | 12.112 h |
| December | 29.1°C24.1°C | 24.1°C | 248 | 28.9 | 12.112 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
- Samarinda in SeptemberIndonesia · 79 kmHigh 30.6°C · Low 23.4°C · 173 mm rain
- Loa Janan in SeptemberIndonesia · 91 kmHigh 30.6°C · Low 23.6°C · 167 mm rain
- Nusantara in SeptemberIndonesia · 150 kmHigh 29.9°C · Low 23.4°C · 155 mm rain
- Balikpapan in SeptemberIndonesia · 172 kmHigh 28.2°C · Low 24.6°C · 109 mm rain
- Tarakan in SeptemberIndonesia · 354 kmHigh 28.4°C · Low 24.9°C · 227 mm rain
- Toli-Toli in SeptemberIndonesia · 384 kmHigh 27.3°C · Low 20.8°C · 171 mm rain
- Majene in SeptemberIndonesia · 440 kmHigh 28.7°C · Low 25.1°C · 41 mm rain
- Tawau in SeptemberMalaysia · 459 kmHigh 29.0°C · Low 24.2°C · 176 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 Bontang) is explained once on the Bontang year overview and on the Sources, method and limits page.