Northern Ireland - United Kingdom weather in September 2025
Northern Ireland - United Kingdom weather in September 2025
Day
16 °C
Night
10 °C
Sea
14 °C
Precipitation
87 mm
in month
Rainy days
15 days
in month
Daylight
13 hours
average
Sunshine
4 hours
average
Humidity
89 %
Day
16 °C
Night
10 °C
Sea
14 °C
Precipitation
87 mm
in month
Rainy days
15 days
in month
Daylight
13 hours
average
Sunshine
4 hours
average
Humidity
89 %
Overview: Northern Ireland - United Kingdom
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Weather charts for Northern Ireland - United Kingdom
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Weather overview and FAQs
Weather overview
In September in Northern Ireland, the average air temperature ranges from 16 °C (61 °F) during the day to 10 °C (49 °F) at night. There are 15 days of rain on average, where the rainfall is 87 mm (3.43 in).
Are there good conditions to visit in September in Northern Ireland?
Northern Ireland can be visited in September - the weather will be moderate. A relatively low temperature of 16 °C (61 °F) may be ideal for walking or outdoor activities, but some people may have a different idea of the holiday. The temperature of 10 °C (49 °F) at night may make it better to dine inside or to put on more clothes for a dinner outside.
What is the temperature in Northern Ireland during the day in September?
In September in Northern Ireland, the average daily temperatures will be 16 °C (61 °F). Nice temperature for walking around the city or on the beach, but you will probably get cold soon when wearing a swimsuit. When walking around all day, people used to cold conditions, pull out their shorts and get rid of their sweaters. On some days, when spending time in the direct sun, sunscreen can be useful, especially for people with more sensitive skin.
What is the rainfall intensity in September in Northern Ireland?
In Northern Ireland in September, there is 87 mm (3.43 in) rainfall, which means on average 3 mm (0.11 in) rainfall per day.
How many days of precipitation on average can I expect in Northern Ireland in September?
In September in Northern Ireland, we can expect 15 days to be rainy, that is, days when precipitation exceeds 2 mm (0.08 in). Converted to days of the week, this means that it will occur on an average of 3.6 days of the week, or in general - 52 % days.
Is Northern Ireland rainier in September than in August?
No, September in Northern Ireland is not a rainier month than August.
What is the air temperature in Northern Ireland in September at night?
The average night temperature in Northern Ireland in September is 10 °C (49 °F). The nights will be cool, layers of clothes will be needed for evening and morning walks, the hotel should be equipped with heating.
How many sunny hours can I expect in Northern Ireland in September?
In September in Northern Ireland, you can expect around 4 hours of sunshine.
Is the weather in Northern Ireland warmer in September than in August?
No, September is not warmer in Northern Ireland than August.
What is the humidity in September in Northern Ireland?
In Northern Ireland in September, expect humidity around 89 %. This humidity is rather above average, but except for sensitive individuals, it should not be a problem.
How long is the day (from dawn till dusk) in Northern Ireland in September?
The length of daylight in Northern Ireland in September is 13 hours.
Is the temperature rising or falling in the course of time in Northern Ireland in September?
During September in Northern Ireland, the day temperatures are decreasing - from 17 °C (63 °F) at the beginning of the month to 15 °C (58 °F) at the end of the month.
How windy is it in September in Northern Ireland?
In September in Northern Ireland, there will be an average wind scale of 5.