Weather in Swansea in May

Shoulder season. May sits in between. You will get good days and you will lose some. Highs sit at 14.8 °C and the day is short; this is an indoors-with-excursions month, not an outdoors-all-day one.

May ranks 5 of 12 in Swansea: past the worst of the year but short of July, which is the month to book if the dates are open.

Rain on 13 days, 2 of them heavy. Enough to need a plan B, not enough to need a plan around it. Layers, and a genuinely waterproof outer — at 14.8 °C the difference between a good day and a miserable one is entirely down to what you are wearing.

What the averages hide

Averages flatten a month, and this one hides a few things: the day barely swings — 5.7 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest May day reached 22.4 °C and the coldest night fell to 4.1 °C, and the wettest single day dropped 30 mm — roughly 42% of the month's rain in one day.

May is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest May on record still delivered 131 mm against 14 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 71 mm average is a reasonable planning figure, not a promise.

Wind is light at 14.1 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 83%, which at 14.8 °C means damp rather than muggy — the kind of cold that gets into a coat and stays there.

How May sits in the year

The month is on the way up: 2.7 °C warmer than April, and June adds another 2.6 °C. Late in the month feels noticeably different from the start of it, which is worth knowing if the trip is short.

Daylight in May

15.6 hours of daylight, gaining 1.5 hours across the month. That is between Swansea's extremes of 16.6 and 7.9 hours, so days are long enough not to constrain the plan.

An inland climate

Despite being inland, the year stays fairly even: 14.8 °C between the year's warmest afternoons and coldest nights.

How busy it gets

Busy. Popular without being frantic; book the things you care about, improvise the rest.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

May in Swansea versus nearby

If Swansea is one option among several, the nearby comparison is worth making. Birmingham is close enough to be a coin toss — within a degree on temperature, 1 day less rain. Manchester is close enough to be a coin toss — within a degree on temperature, 2 days more rain.

So: May works, with July the better month by 10 points if the dates can move. If they cannot, nothing here should stop you booking.

Every month in Swansea

See all twelve months in Swansea, or where else to go in May.