Weather in Cartagena in December

Prime time. If you get to pick your dates, December is the one. Highs average 17.1 °C, lows 10.8 °C, and rain falls on 5 days — nothing in the month is working against you.

Cartagena barely has seasons. December scores 81 out of 100 against a best of 95 in May — a gap small enough that the month you choose matters far less here than the week you choose. Worth keeping in perspective: December is the weakest month of Cartagena's year and it is still a perfectly good one. The downside here is small.

Rain falls on only 5 days, so an itinerary with no wet-weather fallback is a reasonable risk. Pack for 17.1 °C days and 10.8 °C nights; the spread matters more here than any single number.

What the averages hide

The averages here are honest — no hidden extremes worth planning around. Across the twenty years measured, the hottest December day reached 23 °C and the coldest night fell to 2.6 °C, and the wettest single day dropped 72 mm — roughly 195% of the month's rain in one day.

This is the volatile part. December rainfall has ranged from 3 mm to 213 mm across the twenty years measured — a 210 mm spread around an average of 37 mm. The average is real but almost no individual December looks like it, so treat the figure as the middle of a wide range rather than a forecast.

Wind is light at 12.2 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 74%.

How December sits in the year

Temperatures hold steady either side: 19.9 °C in November, 17.1 here, 16.4 in January. Nothing about the timing within the month matters much.

Daylight in December

December sits at the dark end of Cartagena's year — 9.6 hours of daylight against 14.7 at midsummer, holding steady all month. Sightseeing days are genuinely shorter, and an itinerary built for summer will not fit.

Sea temperature

The sea sits at about 16.4 °C in December — cold — a quick dip rather than a swim, and a wetsuit if you are in for longer. The sea peaks at 25.7 °C in August and bottoms out at 14.7 °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

Quiet. Few other visitors, cheaper rooms, and a real chance some seasonal operators are shut.

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

December in Cartagena versus nearby

If Cartagena is one option among several, the nearby comparison is worth making. Murcia is close enough to be a coin toss — within a degree on temperature, 1 day less rain. Valencia is close enough to be a coin toss — within a degree on temperature, the same number of rain days.

So: December works, with May the better month by 14 points if the dates can move. If they cannot, nothing here should stop you booking.

Every month in Cartagena

See all twelve months in Cartagena, or where else to go in December.