The climate in Khong during September can be summarized as hot, humid and very wet.
September is in the fall / autumn in Khong and is typically the 6th coldest month of the year. Daytime maximum temperatures average around a steamy 32°C (89°F), whilst at night 24°C (75°F) is normal.
| Daytime temperature | 31.6°C 88.9°F | 
|---|---|
| Nightly temperature | 23.6°C 74.5°F | 
| Average temperature | 27.6°C 81.7°F | 
| Daily sunshine | 6 hrs | 
| Avg rainfall | 254 mm 10 ins | 
| Rainy days | 19 days | 
| Sea temperature | 28.9°C 84°F | 
| Humidity | 81% | 
| Windspeed | 3.2kph 2 mph | 
On average September is the wettest month of the year in Khong with around 254mm 10 inches of rain making it a very wet time to visit. This rainfall is typically spread over 19 days, although this may vary considerably.
On the flip side this corresponds to an average of 6 hours of sunshine per day.
				
						
						The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in Khong in September 2025.
Best places to visit in September
| Hottest month: | April | 35.9°C 96.6°F | 
|---|---|---|
| Driest month: | December | 2mm 0.1ins | 
| Sunniest month: | December | 9.7hrs | 
| Coldest month: | December | 28.9°C 84°F | 
| Wettest month: | September | 254mm 10ins |