Cilegon, Indonesia climate

As Tropical savanna (dry summer)

Cilegon has a remarkably steady tropical climate (Tropical savanna (dry summer), Köppen As). The hottest month is October with an average daily high near 33°C, while the coldest is February averaging around 24°C at night. Precipitation totals about 981 mm a year and is strongly seasonal — January alone averages 155 mm while August barely receives 25 mm.

☀️ All year

Hot

Daytime highs near 33°C most of the year.

🌙 Nights

Stays warm

Even the coolest nights stay near 24°C.

🌧️ Rain

Moderate rainfall

About 981 mm of rain a year.

Wettest in January

⛅ Sky & trend

Often grey

Overcast skies dominate much of the year.

Temperature & precipitation

Daily high–low temperature range with the monthly average, plus monthly precipitation · 1991–2020 normals · hover a month for the exact figures

Hours of sunshine per day

Estimated sunny hours each month — daylight length × clear-sky fraction · 1991–2020 monthly cloud cover (NASA POWER)

Cilegon climate normals (1991–2020)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Avg high (°C)	31	31	32	32	32	32	32	32	33	33	32	31
Avg temp (°C)	27	27	28	28	28	28	27	27	28	28	28	28
Avg low (°C)	24	24	24	24	24	23	23	23	23	23	24	24
Precipitation (mm)	155	144	114	92	75	46	47	25	38	59	90	96

Jan – Jun	Jan	Feb	Mar	Apr	May	Jun
Avg high (°C)	31	31	32	32	32	32
Avg temp (°C)	27	27	28	28	28	28
Avg low (°C)	24	24	24	24	24	23
Precipitation (mm)	155	144	114	92	75	46

Jul – Dec	Jul	Aug	Sep	Oct	Nov	Dec
Avg high (°C)	32	32	33	33	32	31
Avg temp (°C)	27	27	28	28	28	28
Avg low (°C)	23	23	23	23	24	24
Precipitation (mm)	47	25	38	59	90	96

Sky & atmosphere

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Cloud cover (%)	89	90	84	80	68	61	56	51	58	74	87	91
Relative humidity (%)	85	86	85	84	83	82	80	78	76	77	80	83
Wind speed (mph)	6.4	5.9	5.5	4.9	4.6	4.6	4.5	4.5	4.4	4.5	4.9	6.4

Jan – Jun	Jan	Feb	Mar	Apr	May	Jun
Cloud cover (%)	89	90	84	80	68	61
Relative humidity (%)	85	86	85	84	83	82
Wind speed (mph)	6.4	5.9	5.5	4.9	4.6	4.6

Jul – Dec	Jul	Aug	Sep	Oct	Nov	Dec
Cloud cover (%)	56	51	58	74	87	91
Relative humidity (%)	80	78	76	77	80	83
Wind speed (mph)	4.5	4.5	4.4	4.5	4.9	6.4

Methodology & sources

Temperature & precipitation — 1991–2020 normals computed from 25 years of daily observations at Serang, a weather station, about 14 km from the city centre. The underlying daily records come from NOAA's global station network.

Cloud, humidity, wind & sunshine — modelled estimates from NASA POWER, NASA's satellite-and-reanalysis climatology. This is the standard global source for atmospheric variables, which are not measured at most weather stations.

How we build these numbers →