Weather in Cartagena in May

Shoulder season. May is shoulder season in Cartagena — cheaper, quieter, and a genuine gamble. You should expect rain on 22 days of the month, which is more days wet than dry.

May ranks 9 of 12 in Cartagena: past the worst of the year but short of January, which is the month to book if the dates are open.

Rain on 22 of the month's 31 days, 5 of them heavy. At that frequency a wet-weather backup is not a contingency, it is the itinerary — book the indoor things first and treat the clear days as the bonus. Natural fibres and a second shirt for the day. At 82% nothing dries, including you.

What the averages hide

Averages flatten a month, and this one hides a few things: 14 days top 30 °C — hot spells arrive, but they break; the day barely swings — 2.6 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest May day reached 33.1 °C and the coldest night fell to 25 °C, and the wettest single day dropped 108 mm — roughly 61% of the month's rain in one day.

May is moderately variable: 31 mm in the driest year against 494 mm in the wettest, around an average of 178 mm. Roughly two Mays in three land near that average, and the third does something else entirely.

Wind is light at 13.7 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 82%, high enough to notice on the warm days without dominating them.

How May sits in the year

Temperatures hold steady either side: 30.3 °C in April, 29.8 here, 30.2 in June. Nothing about the timing within the month matters much. Rain has already shifted: 11 days more than April had.

Daylight in May

Cartagena sits close enough to the equator that daylight barely moves all year — 12.6 hours in May, against a range of just 1.2 hours across the whole calendar. Sunrise and sunset land at roughly the same time whenever you come.

Sea temperature

The sea sits at about 28.6 °C in May — warm enough that the water offers no relief from the heat. The sea peaks at 29.3 °C in October and bottoms out at 27.1 °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.

May in Cartagena versus nearby

If Cartagena is one option among several, the nearby comparison is worth making. Barranquilla is close enough to be a coin toss — within a degree on temperature, 2 days less rain. Medellín is a better bet in May — 5.2 °C cooler, 4 days more rain.

So: May is a compromise. January is 36 points better and is what Cartagena 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 Cartagena

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