Click on a day for an hourly weather forecast
The weather in Phnom Penh in September is very hot. The average temperatures are between 25°C and 32°C, drinking water regularly is advisable.
There’s going to be many days of rain during the month of September in Phnom Penh.
Phnom Penh should expect an average of 15 to 22 days of rain, so be sure to bring along a waterproof jacket to stay dry this month!
Our weather forecast can give you a great sense of what weather to expect in Phnom Penh in September 2025.
If you’re planning to visit Phnom Penh in the near future, we highly recommend that you review the 14 day weather forecast for Phnom Penh before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 33° / 22° | 1 | 30 | 0 | 30 mm | Good | Phnom Penh in January |
| February | 35° / 24° | 1 | 27 | 0 | 30 mm | Ok | Phnom Penh in February |
| March | 36° / 26° | 3 | 28 | 0 | 75 mm | Ok | Phnom Penh in March |
| April | 36° / 27° | 10 | 20 | 0 | 223 mm | Bad | Phnom Penh in April |
| May | 35° / 27° | 15 | 16 | 0 | 268 mm | Bad | Phnom Penh in May |
| June | 34° / 26° | 16 | 14 | 0 | 226 mm | Bad | Phnom Penh in June |
| July | 33° / 25° | 15 | 16 | 0 | 206 mm | Ok | Phnom Penh in July |
| August | 33° / 25° | 16 | 15 | 0 | 244 mm | Ok | Phnom Penh in August |
| September | 32° / 25° | 20 | 10 | 0 | 353 mm | Ok | Phnom Penh in September |
| October | 32° / 25° | 16 | 15 | 0 | 363 mm | Ok | Phnom Penh in October |
| November | 31° / 24° | 6 | 24 | 0 | 160 mm | Good | Phnom Penh in November |
| December | 31° / 22° | 3 | 28 | 0 | 69 mm | Good | Phnom Penh in December |