Serang climate

Name: Serang
Address: ID

Serang is warmest in September, with average highs of 31 °C, and coldest in July, when nights average 23 °C. January is the wettest month (277 mm) and August the driest (51 mm). Figures are 1991–2020 climate normals.

Across a full year Serang averages 1,941 mm of rain and 365 days above 25 °C.

Indonesia · population 735,651 · 1991–2020 normals

Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month

Warmest month September 31 °C
Coldest month July 23 °C
Driest month August 51 mm
Wettest month January 277 mm
Least cloud August 58 % cloud
Hottest on record October 36 °C
Coldest on record June 20 °C
Warmest sea May 30 °C

What to expectSerang through the year

Serang changes little through the year. Average daily highs stay between 30 and 31 °C, so no month stands out as a season in the way it would further from the equator.

Counted across a normal year, 365 days a year reach 25 °C, 126 of them reach 30 °C. The warmest reading in the 1991–2020 record is 36 °C, in October.

Rain is strongly seasonal. January averages 277 mm against 51 mm in August — 5.4 times as much. Planning around the dry months matters more here than planning around temperature.

The sea off Serang is warmest in May at 30 °C and coldest in January at 29 °C. Sea temperature lags the air by a month or two, which is why late summer swims warmer than early summer at the same air temperature.

Month by month

Month	Avg high	Rainfall	Cloud
January	28.6 °C	277 mm	89 %
February	28.8 °C	259 mm	90 %
March	29.2 °C	231 mm	85 %
April	29.6 °C	188 mm	80 %
May	29.7 °C	133 mm	69 %
June	29.6 °C	102 mm	62 %
July	29.6 °C	72 mm	60 %
August	30.2 °C	51 mm	58 %
September	31.0 °C	64 mm	64 %
October	31.0 °C	116 mm	73 %
November	30.0 °C	192 mm	84 %
December	28.8 °C	255 mm	90 %

Temperature month by month

Month	Avg high	Avg low	Mean	Record high	Record low	Days above 25 °C	Days above 30 °C
January	28.6 °C	24.0 °C	25.9 °C	31.7 °C	22.5 °C	31	2
February	28.8 °C	24.0 °C	26.0 °C	31.5 °C	21.9 °C	28	2
March	29.2 °C	24.2 °C	26.3 °C	32.3 °C	22.8 °C	31	5
April	29.6 °C	24.3 °C	26.5 °C	32.1 °C	22.1 °C	30	9
May	29.7 °C	24.2 °C	26.6 °C	32.1 °C	21.9 °C	31	11
June	29.6 °C	23.7 °C	26.4 °C	32.1 °C	19.9 °C	30	8
July	29.6 °C	23.3 °C	26.2 °C	32.6 °C	20.3 °C	31	9
August	30.2 °C	23.4 °C	26.6 °C	34.0 °C	20.2 °C	31	16
September	31.0 °C	23.8 °C	27.1 °C	34.3 °C	21.2 °C	30	23
October	31.0 °C	24.3 °C	27.2 °C	35.9 °C	22.1 °C	31	22
November	30.0 °C	24.3 °C	26.6 °C	35.5 °C	21.9 °C	30	14
December	28.8 °C	24.2 °C	26.1 °C	32.9 °C	21.7 °C	31	5

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind	Sea temp
January	277 mm	28	12 h/day	89 %	87 %	15 km/h	28.5 °C
February	259 mm	27	12 h/day	90 %	87 %	14 km/h	28.6 °C
March	231 mm	27	12 h/day	85 %	87 %	13 km/h	29.0 °C
April	188 mm	25	12 h/day	80 %	87 %	12 km/h	29.5 °C
May	133 mm	22	12 h/day	69 %	86 %	11 km/h	29.7 °C
June	102 mm	17	12 h/day	62 %	85 %	11 km/h	29.5 °C
July	72 mm	15	12 h/day	60 %	82 %	11 km/h	29.0 °C
August	51 mm	13	12 h/day	58 %	79 %	12 km/h	28.8 °C
September	64 mm	14	12 h/day	64 %	78 %	12 km/h	29.0 °C
October	116 mm	20	12 h/day	73 %	79 %	12 km/h	29.4 °C
November	192 mm	25	12 h/day	84 %	84 %	13 km/h	29.5 °C
December	255 mm	26	12 h/day	90 %	86 %	15 km/h	29.0 °C

How Serang compares

The same four figures for nearby destinations, so the numbers above have something to be read against. Summer high is the warmest month's average high; winter low is the coldest month's average low.

Destination	Summer high	Winter low	Rain per year	Days above 25 °C
Serang	31 °C	23 °C	1,941 mm	365
Cilegon · Indonesia	30 °C	24 °C	2,154 mm	365
Pasarkemis · Indonesia	32 °C	22 °C	2,170 mm	365
Curug · Indonesia	32 °C	22 °C	2,166 mm	365
Tangerang · Indonesia	32 °C	22 °C	2,068 mm	365
Teluknaga · Indonesia	32 °C	23 °C	2,011 mm	365
Pamulang · Indonesia	32 °C	22 °C	2,115 mm	365

Where Serang ranks

Ranking	Position	Value
Warmest sea temperatures in Asia in November	28th of 50	30 °C
Warmest sea temperatures in the world in November	32nd of 50	30 °C
Warmest sea temperatures in Asia in December	42nd of 50	29 °C

Planning a trip? See the best time to visit Serang.

QuestionsCommon questions about Serang’s climate

When is the best time to visit Serang?

That depends on what you want, so the honest answer is a comparison rather than a single month. January, February, December sit closest to 20 °C on average, September is the warmest month and August the driest. The month-by-month table above has the full picture.

How hot does Serang get?

In September, the warmest month, daily highs average 31 °C. About 126 days a year pass 30 °C. The highest value in the 1991–2020 record is 36 °C.

How cold does it get in winter?

Nights average 23 °C in July, the coldest month. Freezing nights are not part of a normal year here.

Which month is wettest in Serang?

January, averaging 277 mm over 28 days with rain. The driest month is August with 51 mm. The year as a whole averages 1,941 mm.

Are these figures a forecast?

No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in Serang rather than what any particular week will bring. Individual years can differ substantially from the normal.

Data sources and method

ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
Open-Meteo — Open-Meteo.com. CC BY 4.0
NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
GeoNames — GeoNames.org. CC BY 4.0

Normal period: 1991–2020
Data point: -6.115°, 106.154° (the coordinates the reanalysis values are taken for)
Dataset version: era5-1991-2020-scores1.1
Last processed: 1 August 2026

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.