Phnom Penh, Cambodia climate

Am Tropical monsoon

Phnom Penh has a remarkably steady tropical climate (Tropical monsoon, Köppen Am). The hottest month is April with an average daily high near 33°C, while the coldest is January averaging around 23°C at night. Precipitation totals about 2609 mm a year and is strongly seasonal — September alone averages 443 mm while February barely receives 24 mm.

☀️ All year

Hot

Daytime highs near 33°C most of the year.

🌙 Nights

Stays warm

Even the coolest nights stay near 23°C.

🌧️ Rain

Very wet

About 2609 mm of rain a year.

Wettest in September

⛅ 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)

Phnom Penh climate normals (1991–2020)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Avg high (°C)	31	31	32	33	32	31	30	30	30	30	31	31
Avg temp (°C)	27	27	28	29	29	28	28	28	27	27	28	27
Avg low (°C)	23	23	25	25	26	26	25	25	25	24	24	24
Precipitation (mm)	35	24	76	132	230	306	418	411	443	318	147	70

Jan – Jun	Jan	Feb	Mar	Apr	May	Jun
Avg high (°C)	31	31	32	33	32	31
Avg temp (°C)	27	27	28	29	29	28
Avg low (°C)	23	23	25	25	26	26
Precipitation (mm)	35	24	76	132	230	306

Jul – Dec	Jul	Aug	Sep	Oct	Nov	Dec
Avg high (°C)	30	30	30	30	31	31
Avg temp (°C)	28	28	27	27	28	27
Avg low (°C)	25	25	25	24	24	24
Precipitation (mm)	418	411	443	318	147	70

Sky & atmosphere

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Cloud cover (%)	55	49	54	66	83	86	88	88	90	84	71	64
Relative humidity (%)	75	75	77	77	80	82	83	83	84	82	80	77
Wind speed (mph)	7.8	7.8	7.9	7.2	8.2	10.2	11.1	11.6	10.4	8.0	8.6	9.1

Jan – Jun	Jan	Feb	Mar	Apr	May	Jun
Cloud cover (%)	55	49	54	66	83	86
Relative humidity (%)	75	75	77	77	80	82
Wind speed (mph)	7.8	7.8	7.9	7.2	8.2	10.2

Jul – Dec	Jul	Aug	Sep	Oct	Nov	Dec
Cloud cover (%)	88	88	90	84	71	64
Relative humidity (%)	83	83	84	82	80	77
Wind speed (mph)	11.1	11.6	10.4	8.0	8.6	9.1

Methodology & sources

Temperature & precipitation — 1991–2020 normals computed from 29 years of daily observations at Phu Quoc, a weather station, about 182 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 →