Boom Weather in September
What's the weather like in Boom (Flanders) in September 2025?
The climate in Boom during September can be summarized as mild and reasonably dry.
September is in the fall / autumn in Boom and is typically the 4th warmest month of the year. Daytime maximum temperatures average around 20°C (67°F), whilst at night 11°C (51°F) is normal.
| Daytime temperature | 19.6°C 67.3°F |
|---|---|
| Nightly temperature | 10.6°C 51.1°F |
| Average temperature | 15.1°C 59.2°F |
| Daily sunshine | 6 hrs |
| Avg rainfall | 62 mm 2.4 ins |
| Rainy days | 16 days |
| Sea temperature | 17.7°C 63.9°F |
| Humidity | 79% |
| Windspeed | 13.7kph 9 mph |
On average September is the 3rd driest month of the year in Boom with around 62mm 2.4 inches of rain making it a reasonably dry time to visit. This rainfall is typically spread over 16 days, although this may vary considerably.
On the flip side this corresponds to an average of 6 hours of sunshine per day.
September temperatures in Boom
September rainfall
September hourly sunshine
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 Boom in September 2025.
Other monthly averages
Best places to visit in September
Boom weather stats
| Hottest month: | July | 22.3°C 72.1°F |
|---|---|---|
| Driest month: | February | 50mm 2ins |
| Sunniest month: | August | 7.6hrs |
| Coldest month: | January | 4.9°C 40.8°F |
| Wettest month: | November | 78mm 3.1ins |
© Google