Weather in Leiria in May

Prime time. May is about as good as Leiria gets. Highs average 24 °C, lows 12.2 °C, and rain falls on 8 days — nothing in the month is working against you.

May ranks 2 of 12 in Leiria. Only June scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain on 8 days, 1 of them heavy. Enough to need a plan B, not enough to need a plan around it. Nothing specialised needed — this is the month you pack for the trip rather than for the weather.

What the averages hide

The averages here are honest — no hidden extremes worth planning around. Across the twenty years measured, the hottest May day reached 35.8 °C and the coldest night fell to 6.2 °C, and the wettest single day dropped 29 mm — roughly 69% of the month's rain in one day.

May is moderately variable: 1 mm in the driest year against 121 mm in the wettest, around an average of 42 mm. Roughly two Mays in three land near that average, and the third does something else entirely.

Wind is light at 7.9 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 71%.

How May sits in the year

The month is on the way up: 3.4 °C warmer than April, and June adds another 3.3 °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

14.3 hours of daylight, gaining 0.9 hours across the month. That is between Leiria's extremes of 15 and 9.4 hours, so days are long enough not to constrain the plan.

Sea temperature

The sea sits at about 16.3 °C in May — cold — a quick dip rather than a swim, and a wetsuit if you are in for longer. The sea peaks at 19.9 °C in August and bottoms out at 14.3 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

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 Leiria versus nearby

If Leiria is one option among several, the nearby comparison is worth making. Aveiro is close enough to be a coin toss — 3.1 °C cooler, 1 day more rain. Lisbon is close enough to be a coin toss — 5 °C cooler, 2 days less rain.

So: May is effectively as good as it gets here — 6 points behind June, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Leiria

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