The climate in Dublin during September can be summarized as warm and reasonably dry.
September is in the fall / autumn in Dublin and is typically the 4th warmest month of the year. Daytime maximum temperatures average around 25°C (76°F), whilst at night 12°C (53°F) is normal.
| Daytime temperature | 24.7°C 76.4°F |
|---|---|
| Nightly temperature | 11.6°C 52.8°F |
| Average temperature | 18.1°C 64.6°F |
| Daily sunshine | 7.7 hrs |
| Avg rainfall | 75 mm 2.9 ins |
| Rainy days | 8 days |
| Sea temperature | 21.4°C 70.6°F |
| Humidity | 73% |
| Windspeed | 11.9kph 7 mph |
On average September is the 5th driest month of the year in Dublin with around 75mm 2.9 inches of rain making it a reasonably dry time to visit. This rainfall is typically spread over 8 days, although this may vary considerably.
On the flip side this corresponds to an average of 7.7 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 Dublin in September 2025.
Best places to visit in September
| Hottest month: | July | 28.6°C 83.5°F |
|---|---|---|
| Driest month: | February | 53mm 2.1ins |
| Sunniest month: | June | 9.5hrs |
| Coldest month: | January | 0.7°C 33.3°F |
| Wettest month: | July | 105mm 4.1ins |