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Northern Ireland weather in September 2023
- 1616°C max day temperature
- 1717 days with some rainfall
- 99°C min night temperature
- 1313 hours of daylight per day
- 0No heat & humidity
- 9494 mm of monthly rainfall
- 33 (Moderate) UV index
- 1414°C sea temperature
Below are average maximum temperatures at popular destinations in Northern Ireland in September. Select a destination to see more weather parameters.
Recommended for Northern Ireland
The September weather guide for Northern Ireland (Belfast) shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.
Metric (°C / mm) | Imperial (°F / inches)
More about the UK
How warm is it in Northern Ireland in September?
Daytime temperatures usually reach 16°C in Belfast, Northern Ireland in September, falling to 9°C at night.
How sunny is it in Northern Ireland in September?
There are normally 4 hours of bright sunshine each day in Belfast, Northern Ireland in September - that's 30% of daylight hours.
How warm is the sea around Northern Ireland in September?
The average sea temperature around Belfast, Northern Ireland in September is 14°C.
Does it rain in Northern Ireland in September?
There are usually 17 days with some rain in Belfast, Northern Ireland in September and the average monthly rainfall is 94mm.
Northern Ireland September sunrise & sunset times
Browse the sunrise and sunset times for Northern Ireland in September 2023. Select a month to view Northern Ireland sunrise and sunset times for the next 12 months. The Northern Ireland sunrise and sunset times shown below are for Belfast.
|Date||Sunrise times||Sunset times|
|Friday, 1st September 2023||06:30||20:16|
|Friday, 15th September 2023||06:56||19:41|
|Saturday, 30th September 2023||07:23||19:03|
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