Weather in Barranquilla in September

A hard month. September is a hard month in Barranquilla, and worth planning around. You should expect rain on 26 days of the month, which is more days wet than dry.

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

Rain on 26 of the month's 30 days, 4 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 83% nothing dries, including you.

What the averages hide

Averages flatten a month, and this one hides a few things: 21 days top 30 °C, making the heat continuous rather than occasional; the day barely swings — 3.6 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest September day reached 33.5 °C and the coldest night fell to 25 °C, and the wettest single day dropped 96 mm — roughly 57% of the month's rain in one day.

September is moderately variable: 52 mm in the driest year against 431 mm in the wettest, around an average of 168 mm. Roughly two Septembers in three land near that average, and the third does something else entirely.

Wind is light at 10 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 83%, high enough to notice on the warm days without dominating them.

How September sits in the year

Temperatures hold steady either side: 31 °C in August, 30.5 here, 29.9 in October. Nothing about the timing within the month matters much.

Daylight in September

Barranquilla sits close enough to the equator that daylight barely moves all year — 12.2 hours in September, against a range of just 1.3 hours across the whole calendar. Sunrise and sunset land at roughly the same time whenever you come.

Sea temperature

The sea sits at about 29.1 °C in September — warm enough that the water offers no relief from the heat. This is the warmest the water gets all year.

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.

September in Barranquilla versus nearby

If Barranquilla is one option among several, the nearby comparison is worth making. Cartagena is close enough to be a coin toss — within a degree on temperature, the same number of rain days. Medellín is a better bet in September — 5.6 °C cooler, 1 day less rain.

So: September is a compromise. January is 39 points better and is what Barranquilla 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 Barranquilla

See all twelve months in Barranquilla, or where else to go in September.