Londonderry weather in September 2025

Q: How warm is it in Londonderry in September?

Daytime temperatures usually reach 15°C in Londonderry in September, falling to 8°C at night.

Q: How sunny is it in Londonderry in September?

There are normally 3 hours of bright sunshine each day in Londonderry in September - that's 26% of daylight hours.

Q: Does it rain in Londonderry in September?

There are usually 21 days with some rain in Londonderry in September and the average monthly rainfall is 109mm.

Expect 15°C daytime maximum temperatures in the shade with on average 3 hours of sunshine per day in Londonderry in September. Check more long-term weather averages for Londonderry in September before you book your next holiday to Northern Ireland in 2025/2026.

15
15°C max day temperature
3
3 hours of sunshine per day
21
21 days with some rainfall
8
8°C min night temperature
13
13 hours of daylight per day
0
No heat & humidity
109
109 mm of monthly rainfall
3
3 (Moderate) UV index

More about Londonderry

Londonderry by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Recommended for Northern Ireland

National Trust Holidays: 10% off tiny cottages

Sale

Save 10% on tiny cottages with National Trust Holidays
Book breaks to North Wales, Cornwall, Suffolk & beyond
Travel between 1st Jan & 28th Feb 2025 (inclusive)

Go to National Trust Holidays deal >>

Expires at 23:59 on Friday 28th Feb 2025 · View all National Trust Holidays offers

The September weather guide for Northern Ireland (Londonderry) 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 Londonderry in September?

Daytime temperatures usually reach 15°C in Londonderry in September, falling to 8°C at night.

How sunny is it in Londonderry in September?

There are normally 3 hours of bright sunshine each day in Londonderry in September - that's 26% of daylight hours.

Does it rain in Londonderry in September?

There are usually 21 days with some rain in Londonderry in September and the average monthly rainfall is 109mm.

Londonderry September sunrise & sunset times

Browse the sunrise and sunset times for Londonderry in September 2025. Select a month to view Londonderry sunrise and sunset times for the next 12 months.

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec