Month by month
Bali in September
Drier than July, more reliable than July, and without July's crowd.
September is the one month in the Bali year that is not a trade. It beats July on rainfall and on odds, and July is peak season.
Every other quiet month asks you to give something up for the emptiness: a millimetre a day, a wider gamble, a wetter ceiling. September does not. It averages 49mm, it came in dry in 27 of the last thirty years, which is the second-best figure in the year behind August, and the northern-hemisphere school holidays that fill the island in July have finished.
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What September actually measures
September sits at the bottom of the chart, in the run of months where the bar has stopped being the thing that decides a trip.
Rainfall
49 mm
On average. An independent check at the same point puts it at 38mm.
Dry years
27 of 30
Under 100mm. The second-best figure of the twelve, behind August.
Wettest year
196 mm
Higher than June’s 172mm, which is the one thing June does better.
The monthly average has two independent sources behind it and they agree to within three per cent. The dry-year count and the wettest year come from the reanalysis alone, because the product we check against publishes a climatology rather than a year-by-year series. The 100mm line is ours, about three millimetres a day. As on the other month pages there is no count of rainy days and no separate figure by region.
The month that beats July
Choosing a quiet month over a peak month is normally a trade, and the other pages here put a price on it: June costs you under a millimetre of rain a day for the whole of the peak's crowd, April costs you a wider gamble. September is the exception.
September averages 1.63mm of rain a day. July averages 1.65mm. September came in under 100mm in 27 of the last thirty years; July managed 25. So September is very slightly drier and meaningfully more reliable, and it is the shoulder month while July is the peak. Run that comparison across every shoulder month against every peak month and this is the only pairing where the quiet one wins on both.
The differences are small in absolute terms, and that is the point rather than a caveat. Nobody can feel two hundredths of a millimetre a day. What they can feel is a temple without a queue at it, a road that takes the time the map says, and a room that did not need booking six months out. September hands over all of that and asks for nothing back.
The one thing June does better
There is a single axis on which September loses to the other great shoulder month, and it is worth knowing because it only shows up in a bad year. The wettest September in thirty was 196mm. The wettest June was 172mm. A single trip is one year rather than thirty, so the ceiling matters alongside the odds, and September's is the higher of the two.
In practice that reads as: September has the better odds and June has the better worst case. If your trip can absorb a wet week but you would rather it did not happen, take September. If a wet week would wreck the whole thing, June's ceiling is the more comfortable one to sit under. Both are far better bets than any month in the wet season.
Where to base yourself in September
Everything is open and nothing is full, which is a combination the calendar offers twice a year at most. The west coast is still working, so Uluwatu and the Bukit hold their season; Canggu and Seminyak have emptied out since August; and the highlands around Munduk and Kintamani still have dry-season odds on a view.
The east coast is the one that gains most. Amed and the diving off Tulamben want calm water and clear visibility, and September supplies both without the boats and the dive shops being at capacity. So does Nusa Penida, where a night on the island rather than a rushed day trip is easier to justify now than at any other point in the year.
All twelve bases, with what the airport transfer costs to each, are on our where to stay in Bali page.
What September is good for
The trip that needs both the weather and the space. A Mount Batur sunrise with dry-season odds and a trailhead that is not a car park. The Bukit reefs in season and not shoulder to shoulder; our surfing guide has the seasonal switch. A split stay that pairs the coast with the mountains, which the wet season makes a gamble and September does not.
What it does not give you is the green. By September the island has been drying for five months, so the rice terraces and the waterfalls are near their thinnest, as they are in August. If the landscape is the reason for the trip rather than the sea, January is the month that flatters it, and it charges rain for the privilege.
For how September sits against the other eleven on crowds as well as rain, see when to visit, and our weather guide for the pattern across the year.
Every month of the Bali year, with its measured rainfall and what the average hides, is on Bali month by month.
Bali in September: common questions
What is the weather like in Bali in September?+
Dry-season weather, and close to the best of it. September averages 49mm in the southern lowlands and came in under 100mm in 27 of the last thirty years, which is the second-highest figure of any month behind August. Daytime highs are 30.1C and nights 23.7C, among the coolest of the year.
Is September a good time to visit Bali?+
It is one of the two best months on the calendar and arguably the best value on it. September is drier per day than July and came in dry in more years than July did, and July is peak season. That makes it the one month in the Bali year where choosing the quiet option costs you nothing on the weather.
Is September better than July in Bali?+
On the record, yes, on both counts. September averages 1.63mm of rain a day against July's 1.65mm, and it came in dry in 27 of thirty years against 25. It also has a fraction of the crowd, because the northern-hemisphere school holidays have finished. There is no axis on which July wins.
How often is September dry in Bali?+
In 27 of the last thirty years it delivered under 100mm, our threshold for calling a month dry. Only August does better, at 29 of thirty. The wet-season months manage between none and three, so September is close to a safe bet without being a certainty.
How hot is Bali in September?+
About 30.1C by day and 23.7C at night, near the cool end of a range that spans barely two and a half degrees across the whole year. September's nights are the joint coolest, shared with August. Nobody notices this on their skin; it is worth saying only because people expect the dry season to be the hot season, and in Bali it is the reverse.
Is the surf still good in Bali in September?+
Yes. The southeast trades are still blowing offshore on the west coast, so the Bukit reefs at Uluwatu, Padang Padang, Bingin and Balangan are working, and the crowd that fills them in July and August has gone home. For a surf trip that wants the season without the queue, September is the pick.
Are the boats to Nusa Penida reliable in September?+
Among the most reliable of the year. The fast boats from Sanur are cancelled when the sea is rough, and rough days remain scarce through September. An island day, or a night on the island, can sit anywhere in the trip rather than being nursed through it.