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 91°F, while the coldest is January averaging around 74°F at night. Precipitation totals about 103 inches a year and is strongly seasonal — September alone averages 17.5 inches while February barely receives 0.94 inches.

☀️ All year

Hot

Daytime highs near 91°F most of the year.

🌙 Nights

Stays warm

Even the coolest nights stay near 74°F.

🌧️ Rain

Very wet

About 103 in 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 (°F)	87	88	90	91	90	88	86	86	86	87	88	87
Avg temp (°F)	81	81	83	84	84	83	82	82	81	81	82	81
Avg low (°F)	74	74	76	78	78	78	77	78	77	76	76	75
Precipitation (in)	1.4	0.9	3.0	5.2	9.0	12.0	16.4	16.2	17.5	12.5	5.8	2.7

Jan – Jun	Jan	Feb	Mar	Apr	May	Jun
Avg high (°F)	87	88	90	91	90	88
Avg temp (°F)	81	81	83	84	84	83
Avg low (°F)	74	74	76	78	78	78
Precipitation (in)	1.4	0.9	3.0	5.2	9.0	12.0

Jul – Dec	Jul	Aug	Sep	Oct	Nov	Dec
Avg high (°F)	86	86	86	87	88	87
Avg temp (°F)	82	82	81	81	82	81
Avg low (°F)	77	78	77	76	76	75
Precipitation (in)	16.4	16.2	17.5	12.5	5.8	2.7

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 →