SeasonMapRaja Ampat (Waisai) weather in September
Indonesia
September in Raja Ampat: sweltering, soaked, with clean air — fine if you can take 25 rainy days.
#3 of 12 months in Raja Ampat · #926 of 1383 destinations to visit in September · comfort 71/100 (tier B)
Updated September 2026 · climate normals from ERA5 reanalysis
Traveller notes on Raja Ampat in September
Other months in Raja Ampat
Raja Ampat's forum rates the October-through-April window as the best overall, with October itself a genuine transition month — the strong south winds of July-September starting to calm, though rain can still turn up as the wet season approaches. Regulars flag October as a good stretch for marine life, with bait-fish schools and manta activity drawing divers to the sites.
Add your own note from Raja Ampat's card on the map.
Raja Ampat climate normals — September
| Daytime high | 28°C / 83°F | 🔥 sweltering |
|---|---|---|
| Nighttime low | 25°C / 78°F | |
| Feels like (high) | 34°C / 93°F | |
| Sea temperature | 30°C / 86°F | ♨️ bath-warm |
| Rainfall | 305 mm / 12 in | ⛈ soaked |
| Rainy days | 25 days | |
| Humidity | 83% | 💦 very humid |
| Dew point | 24°C / 74°F | |
| Sunshine | 9.9 h/day | |
| Daylight | 12.1 h | |
| Wind | 12 km/h / 8 mph | |
| Air quality (US AQI) | 21 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Raja Ampat in September
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
Busyschool holidays in 3 of the markets that fill it, one of its best months for weather(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for Raja Ampat's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Fair weatherRaja Ampat's weather doesn't swing hard through the year — comfort stays fairly steady in every month.
What's on in Raja Ampat in September
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Rule
Marine park entry permit
1 Jan – 31 DecEvery visitor buys an entry tag valid for a calendar year, either online beforehand or at the authority office in Waisai. It funds the patrols, and it is checked on the boats. Source ↗
- Season
Windy season
15 Jun – 30 Sep · usuallyWind seasonRiskThe southeast wind builds a short steep chop across the open crossings and the small boats stop running on the worst days. A number of homestays simply close for it.
- Season
Wet season
MonsoonRisk25 rainy days and about 305 mm in the month — the real kind of rainy season, not afternoon showers.
from the climate normals
Where is Raja Ampat?
Raja Ampat in September — FAQ
- Is September a good time to visit Raja Ampat?
- September in Raja Ampat: sweltering, soaked, with clean air — fine if you can take 25 rainy days. It ranks #3 of 12 months for Raja Ampat on SeasonMap's comfort score (71/100).
- What is the weather like in Raja Ampat in September?
- In September, Raja Ampat averages a daily high of 28.3°C and a low of 25.4°C, with about 305.3 mm of rain over roughly 24.5 rainy days.
- What is the air quality in Raja Ampat in September?
- Raja Ampat has a mean US Air Quality Index of about 21 in September.