Northern Ireland weather in May 2025

Q: How warm is it in Northern Ireland in May?

Daytime temperatures usually reach 14°C in Belfast, Northern Ireland in May, falling to 6°C at night.

Q: How sunny is it in Northern Ireland in May?

There are normally 6 hours of bright sunshine each day in Belfast, Northern Ireland in May - that's 37% of daylight hours.

Q: Is the sea cold around Northern Ireland in May?

The average sea temperature around Belfast, Northern Ireland in May is 9°C.

Q: Does it rain in Northern Ireland in May?

There are usually 16 days with some rain in Belfast, Northern Ireland in May and the average monthly rainfall is 65mm.

Expect 14°C daytime maximum temperatures in the shade with on average 6 hours of sunshine per day in Northern Ireland in May. Check more long-term weather averages for Northern Ireland in May before you book your next holiday to Northern Ireland in 2025/2026.

14
14°C max day temperature
6
6 hours of sunshine per day
16
16 days with some rainfall
6
6°C min night temperature
16
16 hours of daylight per day
0
No heat & humidity
65
65 mm of monthly rainfall
5
5 (Moderate) UV index
9
9°C sea temperature

More about Northern Ireland

Northern Ireland by month

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

Recommended for Northern Ireland

Marriott discount code: up to 20% off long hotel stays

Discount Code

Save up to 20% when you book long stays with Marriott
20% off - 4-6 nights, 15% off 3 nights
Book participating hotels in Europe, the Middle East & Africa

Show discount code

******UK8

Redeem Marriott discount code >>

View all Marriott offers

The May 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.

Top Northern Ireland destinations

Below are average maximum temperatures at popular countries, regions and places in Northern Ireland in May. Select a holiday destination to see more weather parameters.

14
Belfast
14
Londonderry

All Northern Ireland destinations

Metric (°C / mm) | Imperial (°F / inches)

More about the UK

How warm is it in Northern Ireland in May?

Daytime temperatures usually reach 14°C in Belfast, Northern Ireland in May, falling to 6°C at night.

How sunny is it in Northern Ireland in May?

There are normally 6 hours of bright sunshine each day in Belfast, Northern Ireland in May - that's 37% of daylight hours.

Is the sea cold around Northern Ireland in May?

The average sea temperature around Belfast, Northern Ireland in May is 9°C.

Does it rain in Northern Ireland in May?

There are usually 16 days with some rain in Belfast, Northern Ireland in May and the average monthly rainfall is 65mm.

Northern Ireland May sunrise & sunset times

Browse the sunrise and sunset times for Northern Ireland in May 2025. 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.

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