Weather in Limón in September

Shoulder season. September sits in between. You will get good days and you will lose some. You should expect rain on 29 days of the month, which is more days wet than dry.

Limón barely has seasons. September scores 50 out of 100 against a best of 64 in February — a gap small enough that the month you choose matters far less here than the week you choose.

Rain on 29 of the month's 30 days, 8 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 87% nothing dries, including you.

What the averages hide

Averages flatten a month, and this one hides a few things: the day barely swings — 3.4 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest September day reached 31.1 °C and the coldest night fell to 23.4 °C, and the wettest single day dropped 91 mm — roughly 35% of the month's rain in one day.

September is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest September on record still delivered 547 mm against 91 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 260 mm average is a reasonable planning figure, not a promise.

Wind is light at 3.3 km/h, so the temperature on the page is close to the temperature on your skin, and humidity at 87% is the real story though — it is the number that decides how the day feels, not the 28.9 °C.

How September sits in the year

Temperatures hold steady either side: 28.7 °C in August, 28.9 here, 28.6 in October. Nothing about the timing within the month matters much.

Daylight in September

Limón sits close enough to the equator that daylight barely moves all year — 12.2 hours in September, 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 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 Limón versus nearby

If Limón is one option among several, the nearby comparison is worth making. San Isidro is close enough to be a coin toss — 2.5 °C cooler, 3 days less rain. San José is a better bet in September — 5.6 °C cooler, 2 days less rain.

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

Every month in Limón

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