Weather in Leiria in January

Shoulder season. January is shoulder season in Leiria — cheaper, quieter, and a genuine gamble. Highs sit at 14.9 °C and the day is short; this is an indoors-with-excursions month, not an outdoors-all-day one.

January ranks 12 of 12 — near the bottom of Leiria's year. June is the month that works, and the swing between the two is 32 points, which is a different holiday rather than a slightly better one.

Rain on 12 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Layers, and a genuinely waterproof outer — at 14.9 °C the difference between a good day and a miserable one is entirely down to what you are wearing.

What the averages hide

The averages here are honest — no hidden extremes worth planning around. Across the twenty years measured, the hottest January day reached 22 °C and the coldest night fell to -2.2 °C, and the wettest single day dropped 35 mm — roughly 42% of the month's rain in one day.

January is moderately variable: 2 mm in the driest year against 190 mm in the wettest, around an average of 84 mm. Roughly two Januarys in three land near that average, and the third does something else entirely.

Wind is light at 7.1 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 85%, which at 14.9 °C means damp rather than muggy — the kind of cold that gets into a coat and stays there.

How January sits in the year

Temperatures hold steady either side: 15.4 °C in December, 14.9 here, 16 in February. Nothing about the timing within the month matters much.

Daylight in January

January sits at the dark end of Leiria's year — 9.6 hours of daylight against 15 at midsummer, gaining 0.7 hours across the month. Sightseeing days are genuinely shorter, and an itinerary built for summer will not fit.

Sea temperature

The sea sits at about 14.9 °C in January — 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

Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.

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

January 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 — within a degree on temperature, 1 day more rain. Lisbon is close enough to be a coin toss — within a degree on temperature, 2 days less rain.

So: January is a compromise. June is 32 points better and is what Leiria is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Leiria

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