Phnom Penh is rarely comfortable to be outside at midday. It comes closest in mid January, and even then it is too hot. For sun, aim for late November to early February.
When to go five ratings · thirty-six ten-day sections · click a cell to read it
For sun, go from late November to early February. It peaks in mid December, at 67. Avoid late April for this: it falls to 19, mostly because it is too hot. The clearest skies come in January, when the sky is typically 38% covered at midday (partly cloudy).
Phnom Penh never quite rates Good for being outside. It comes closest in mid January, at 40, mostly because it is too hot. The weakest stretch is from late April to early May, when it drops to 2, mostly because it is too hot.
Walking is not what Phnom Penh is for: the Active outdoors rating tops out at 12, mostly because it is too warm.
The year, measured
The average temperature in Phnom Penh over the whole year is 29°C. April is the hottest month, with highs of about 34°C; January is the coldest, with lows of about 23°C. The rainy (wet) season in Phnom Penh runs from September to November, peaking in October with a 16% chance of rain on a given day. The dry season is December to June; March is the driest month, at 1%. Winds in Phnom Penh are highest in July, averaging 2.3 m/s (8 km/h), and lightest in October, at 1.4 m/s (5 km/h). The prevailing wind is from the S. The clearest skies in Phnom Penh come in February, when the sky is typically 32% covered; September is the cloudiest month, at 58%.
Month by month Phnom Penh climate by month: average temperatures year round · click a month to read it
| Month | High | Low | Feels like | Chance of rain | Cloud | Wind | Being outside | Sun | Walking |
|---|---|---|---|---|---|---|---|---|---|
| January | 30°C | 23°C | 30°C | 2% | 34% | 1.8 m/s | 36 | 64 | 9 |
| February | 31°C | 24°C | 32°C | 1% | 32% | 1.9 m/s | 21 | 55 | 3 |
| March | 33°C | 25°C | 34°C | 1% | 35% | 2.0 m/s | 13 | 39 | 1 |
| April | 34°C | 27°C | 36°C | 2% | 43% | 2.0 m/s | 8 | 29 | 0 |
| May | 34°C | 27°C | 36°C | 6% | 51% | 1.8 m/s | 9 | 25 | 1 |
| June | 33°C | 27°C | 35°C | 8% | 54% | 2.0 m/s | 15 | 27 | 3 |
| July | 32°C | 26°C | 34°C | 9% | 57% | 2.3 m/s | 19 | 35 | 4 |
| August | 33°C | 27°C | 36°C | 6% | 55% | 2.1 m/s | 11 | 32 | 0 |
| September | 31°C | 26°C | 34°C | 13% | 58% | 1.8 m/s | 21 | 36 | 4 |
| October | 31°C | 26°C | 34°C | 16% | 56% | 1.4 m/s | 21 | 39 | 2 |
| November | 31°C | 25°C | 32°C | 9% | 50% | 1.7 m/s | 27 | 47 | 7 |
| December | 30°C | 24°C | 30°C | 2% | 42% | 2.1 m/s | 34 | 66 | 8 |
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short Phnom Penh weather by season
Year round, Phnom Penh has days of about 30°C at their warmest in December, its coolest month, and 34°C in April, its warmest; the coolest hours of the day run from 23°C to 27°C through the year, and the average temperature over the year is 29°C around the clock. Rain is most likely around October and least likely around March. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
Phnom Penh weather in winterDecember to February
Winter in Phnom Penh has typical daily highs of about 30°C and lows of about 24°C, with a 2% chance of rain on a given day.
Phnom Penh weather in springMarch to May
Spring in Phnom Penh has typical daily highs of about 34°C and lows of about 27°C, with a 3% chance of rain on a given day.
Phnom Penh weather in summerJune to August
Summer in Phnom Penh has typical daily highs of about 32°C and lows of about 27°C, with a 8% chance of rain on a given day.
Phnom Penh weather in autumnSeptember to November
Autumn in Phnom Penh has typical daily highs of about 31°C and lows of about 26°C, with a 13% chance of rain on a given day.
When is the rainy season in Phnom Penh?
The rainy (wet) season in Phnom Penh runs from September to November, peaking in October with a 16% chance of rain on a given day. The dry season is December to June; March is the driest month, at 1%.
What time of year is Phnom Penh windiest?
Winds in Phnom Penh are highest in July, averaging 2.3 m/s (8 km/h), and lightest in October, at 1.4 m/s (5 km/h). The prevailing wind is from the S.
What is the average temperature in Phnom Penh year round?
The average temperature in Phnom Penh over the whole year is 29°C. April is the hottest month, with highs of about 34°C; January is the coldest, with lows of about 23°C.
Where to go instead in late April, the weakest time here for being outside
How this is worked out
Every figure is a decade of weather-station observations blended into one typical year, in ten-day sections. The ratings, the chart and the feels-like column are read at midday local solar time. Being outside is the Easy outdoors rating, Sun is Sunbathing and Walking is Active outdoors, each out of 100: Good from 55, Ideal from 80. They describe what a time of year is usually like here, not a forecast. The dotted links open the map at that time of year; set its time of day to midday to see these numbers.