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The weather in September in Northern Ireland
It's cool to moderate in September in Northern Ireland with an average temperature of 17°C. Temperatures this month range from a low of 15°C to a high of 19°C. At night, you can expect temperatures between 9°C and 13°C.
Looking for sun and warm weather? September isn’t a good month to be in Northern Ireland. The temperatures are too low for a warm stay this month.
Average temperatures and precipitation
This chart shows the average daily maximum and minimum temperatures (in degrees Celsius) and precipitation (in millimeters) in September for Northern Ireland. A low precipitation value usually indicates little to no rainfall on that day in recent years, while a higher value suggests more frequent rainfall.
Temperature records
With 25°C in 2023, Northern Ireland reached the highest temperature in September over the past 10 years. The lowest daytime temperature in this month was 10°C in 2018. The extreme nighttime temperatures ranged from a lowest recorded value of 3°C to a highest value of 17°C.
Rainfall amount
In September, there is an average of 71 mm of precipitation, spread over 9 days. The wind speed is around 4 Bft, mostly coming from the South.
Daily weather in September for Northern Ireland
Click on any day in September to get detailed info about the usual weather on that day in Northern Ireland. Check out the historical temperatures and precipitation over the past 10 years on this day.
September weather comparison
| Northern Ireland | New York | |
|---|---|---|
| Average temperature | 17°C | 27°C |
| Max. temperature | 19°C | 31°C |
| Min. temperature | 9°C | -5°C |
| Total precipitation | 71 mm | 57 mm |
| Rainy days | 9 days | 9 days |
Start of September
The month of September starts in Northern Ireland with mild temps, averaging around 18°C during the day and nights around 13°C.
Mid September
By mid-September, daytime temps drop to around 17°C, with nights around 11°C. There’s a chance of some showers during this time, but plenty of dry and sunny days too.
End of September
By the end of September, the average daytime temperature in Northern Ireland is around 16°C, while nighttime temps are about 10°C. A shower might pop up, but overall, the weather will be dry and sunny.
Find affordable vacations to Northern Ireland
UV index
The UV index is a maximum of 5 this month. That's a moderate value on the intensity scale of 1 to 11. Unprotected skin can burn in about 30 minutes.
Check out the climate of Northern Ireland for all months and discover the best travel time
You can check out all destinations in Northern Ireland to get the full picture of the climate.
Temperature charts
These charts show the average temperatures in September in Northern Ireland. The temperatures are shown in degrees Celsius and are calculated based on data from the past 10 years.
Daily Temperature in September in Northern Ireland
Temperature in September in Northern Ireland over the years
Precipitation charts
These charts show the average amount of precipitation in September in Northern Ireland. Precipitation is always measured as water, even when it falls as snow or hail The amount of precipitation is displayed in millimeters, while snowfall is shown in centimeters.
Daily Precipitation in September in Northern Ireland
Total precipitation in September in Northern Ireland over the years
Daily UV index in September in Northern Ireland
This chart shows the average daily UV index in September in Northern Ireland, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Weather experiences in September in Northern Ireland
The weather in September in Northern Ireland is rated 3 out of 5 stars by 1 visitor. Have you been to Northern Ireland? Share your weather experience to help other visitors.
Write your own review
Sometimes too cold for this time of year, the temperature was usually around 15 degrees. There was occasional rain and clouds, but there were also moments of beautiful sunshine. An umbrella is a must!— This text is automatically translated to English
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Average weather in Northern Ireland by month
Click on a month below to see detailed weather info for Northern Ireland. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.