Portstewart weather in May 2025

Q: How warm is it in Portstewart in May?

Daytime temperatures usually reach 13°C in Portstewart in May, falling to 6°C at night.

Q: How sunny is it in Portstewart in May?

There are normally 6 hours of bright sunshine each day in Portstewart in May - that's 35% of daylight hours.

Q: Is the sea cold around Portstewart in May?

The average sea temperature around Portstewart in May is 9°C.

Q: Does it rain in Portstewart in May?

There are usually 17 days with some rain in Portstewart in May and the average monthly rainfall is 66mm.

Expect 13°C daytime maximum temperatures in the shade with on average 6 hours of sunshine per day in Portstewart in May. Check more long-term weather averages for Portstewart in May before you book your next holiday to Northern Ireland in 2025/2026.

13
13°C max day temperature
6
6 hours of sunshine per day
17
17 days with some rainfall
6
6°C min night temperature
16
16 hours of daylight per day
0
No heat & humidity
66
66 mm of monthly rainfall
5
5 (Moderate) UV index
9
9°C sea temperature

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The May weather guide for Northern Ireland (Portstewart) 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)