Nusantara weather in September
Temperature, sea and sunshine in September: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in September
Good
Best time to visit: January – December
What is the weather like in Nusantara in September?
In September, Nusantara is hot: daytime highs average 30 °C, and even at night it stays warm at around 23 °C. The sea averages 28.7 °C – lovely and warm for swimming. Expect around 6 hours of sunshine a day. It is the rainy season: rain falls on about 20 days, totalling 177 mm. On about 14 days the thermometer climbs to 30 °C or more. The air is often humid and muggy. All in all, September is a good month for a holiday in Nusantara.
September compared
How the weather changes from August to October. Tap a month to open it.
| AugustAug | SeptemberSep | OctoberOct | |
|---|---|---|---|
| Score | 69 | 69 | 67 |
| Day | 29° | 30° | 30° |
| Night | 23° | 23° | 24° |
| Sea | 29° | 29° | 29° |
| Sun | 6 h | 6 h | 5 h |
| Rain days | 22 | 20 | 24 |
More details for September
- Daylight
- 12 h 6 min06:05 – 18:12
- UV index
- 14 · extremeclear sky, noon (estimate)All months
- Muggy days
- 30 daysdew point 18 °C or moreAll months
- Wind
- 10 km/haverage daily peakAll months
- Cloud cover
- 76 %on averageAll months
- Hot days
- 14 days30 °C or moreAll months
- Time zone
- UTC+8Asia/Makassar
How the score comes together
- Temperatureweight 35 %100 %
- Seaweight 25 %100 %
- Sunshineweight 20 %45 %
- Few rainy daysweight 20 %0 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.
What to pack in September
- Swimwear
- Sunscreen
- Sunglasses & sun hat
- Light, breathable clothes
- Water bottle – drink plenty
- Insect repellent
- Rain jacket or umbrella
Nusantara in September: quick answers
Is Nusantara hot in September?
Yes. In September, Nusantara is hot: daytime highs average 30 °C and nights stay around 23 °C. On about 14 days the thermometer climbs to 30 °C or more.
Can you swim in Nusantara in September?
Yes. In September the sea averages 28.7 °C – lovely and warm for swimming.
Does it rain much in Nusantara in September?
It rains often – on about 20 days, adding up to 177 mm.
Nusantara month by month
The whole year in NusantaraAll destinations: IndonesiaWhere to go in SeptemberSea temperature in September
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences