Cotonou climate

Name: Cotonou
Address: BJ

Cotonou is warmest in March, with average highs of 30 °C, and coldest in August, when nights average 24 °C. June is the wettest month (228 mm) and January the driest (30 mm). Figures are 1991–2020 climate normals.

Across a full year Cotonou averages 1,263 mm of rain and 363 days above 25 °C.

Benin · population 679,012 · 1991–2020 normals

Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month

Warmest month March 30 °C
Coldest month August 24 °C
Driest month January 30 mm
Wettest month June 228 mm
Least cloud December 39 % cloud
Hottest on record February 34 °C
Coldest on record January 21 °C
Warmest sea May 29 °C

What to expectCotonou through the year

Cotonou has a clear annual cycle: average daily highs run from 26 °C in August to 30 °C in March, a swing of 3.5 °C in mean temperature across the year.

Counted across a normal year, 363 days a year reach 25 °C, 57 of them reach 30 °C. The warmest reading in the 1991–2020 record is 34 °C, in February.

Rain is strongly seasonal. June averages 228 mm against 30 mm in January — 7.7 times as much. Planning around the dry months matters more here than planning around temperature.

The sea off Cotonou is warmest in May at 29 °C and coldest in August at 25 °C. Sea temperature lags the air by a month or two, which is why late summer swims warmer than early summer at the same air temperature.

Month by month

Month	Avg high	Rainfall	Cloud
January	29.5 °C	30 mm	48 %
February	29.9 °C	40 mm	56 %
March	30.1 °C	71 mm	68 %
April	29.8 °C	97 mm	74 %
May	29.0 °C	172 mm	80 %
June	27.5 °C	228 mm	81 %
July	26.4 °C	136 mm	81 %
August	26.1 °C	92 mm	79 %
September	26.8 °C	138 mm	80 %
October	27.8 °C	150 mm	72 %
November	28.8 °C	74 mm	52 %
December	29.3 °C	35 mm	39 %

Temperature month by month

Month	Avg high	Avg low	Mean	Record high	Record low	Days above 25 °C	Days above 30 °C
January	29.5 °C	25.2 °C	27.1 °C	34.0 °C	20.7 °C	31	7
February	29.9 °C	26.1 °C	27.7 °C	34.3 °C	22.4 °C	28	12
March	30.1 °C	26.7 °C	28.1 °C	31.8 °C	22.0 °C	31	17
April	29.8 °C	26.6 °C	28.0 °C	32.0 °C	24.3 °C	30	12
May	29.0 °C	25.9 °C	27.4 °C	31.2 °C	23.7 °C	31	4
June	27.5 °C	24.8 °C	26.0 °C	30.1 °C	23.1 °C	30	0
July	26.4 °C	24.0 °C	25.0 °C	28.9 °C	22.4 °C	30	0
August	26.1 °C	23.6 °C	24.6 °C	28.1 °C	21.5 °C	30	0
September	26.8 °C	24.1 °C	25.2 °C	28.9 °C	22.9 °C	30	0
October	27.8 °C	24.8 °C	26.1 °C	29.9 °C	23.0 °C	31	0
November	28.8 °C	25.7 °C	27.1 °C	30.9 °C	23.2 °C	30	1
December	29.3 °C	25.6 °C	27.3 °C	32.8 °C	22.0 °C	31	5

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind	Sea temp
January	30 mm	8	12 h/day	48 %	80 %	16 km/h	27.7 °C
February	40 mm	10	12 h/day	56 %	82 %	17 km/h	28.2 °C
March	71 mm	16	12 h/day	68 %	81 %	18 km/h	28.7 °C
April	97 mm	18	12 h/day	74 %	82 %	17 km/h	28.8 °C
May	172 mm	24	12 h/day	80 %	83 %	15 km/h	29.0 °C
June	228 mm	26	12 h/day	81 %	85 %	16 km/h	27.7 °C
July	136 mm	20	12 h/day	81 %	85 %	18 km/h	25.7 °C
August	92 mm	15	12 h/day	79 %	86 %	18 km/h	24.8 °C
September	138 mm	22	12 h/day	80 %	86 %	16 km/h	25.9 °C
October	150 mm	24	12 h/day	72 %	85 %	14 km/h	27.4 °C
November	74 mm	18	12 h/day	52 %	83 %	14 km/h	28.6 °C
December	35 mm	9	12 h/day	39 %	82 %	15 km/h	28.3 °C

How Cotonou compares

The same four figures for nearby destinations, so the numbers above have something to be read against. Summer high is the warmest month's average high; winter low is the coldest month's average low.

Destination	Summer high	Winter low	Rain per year	Days above 25 °C
Cotonou	30 °C	24 °C	1,263 mm	363
Abomey-Calavi · Benin	30 °C	23 °C	1,210 mm	362
Porto-Novo · Benin	31 °C	23 °C	1,274 mm	362
Ota · Nigeria	33 °C	22 °C	1,642 mm	361
Ajegunle · Nigeria	31 °C	24 °C	1,515 mm	362
Agege · Nigeria	32 °C	23 °C	1,497 mm	362
Lagos · Nigeria	31 °C	24 °C	1,589 mm	362

Where Cotonou ranks

Ranking	Position	Value
Warmest sea temperatures in Africa in May	10th of 50	29 °C
Warmest sea temperatures in Africa in November	12th of 50	29 °C
Warmest sea temperatures in Africa in June	17th of 50	28 °C
Warmest sea temperatures in Africa in December	21st of 50	28 °C
Warmest sea temperatures in Africa in February	23rd of 50	28 °C
Warmest sea temperatures in Africa year-round	23rd of 50	28 °C

Planning a trip? See the best time to visit Cotonou.

QuestionsCommon questions about Cotonou’s climate

When is the best time to visit Cotonou?

That depends on what you want, so the honest answer is a comparison rather than a single month. July, August, September sit closest to 20 °C on average, March is the warmest month and January the driest. The month-by-month table above has the full picture.

How hot does Cotonou get?

In March, the warmest month, daily highs average 30 °C. About 57 days a year pass 30 °C. The highest value in the 1991–2020 record is 34 °C.

How cold does it get in winter?

Nights average 24 °C in August, the coldest month. Freezing nights are not part of a normal year here.

Which month is wettest in Cotonou?

June, averaging 228 mm over 26 days with rain. The driest month is January with 30 mm. The year as a whole averages 1,263 mm.

Are these figures a forecast?

No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in Cotonou rather than what any particular week will bring. Individual years can differ substantially from the normal.

Data sources and method

ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
Open-Meteo — Open-Meteo.com. CC BY 4.0
NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
GeoNames — GeoNames.org. CC BY 4.0

Normal period: 1991–2020
Data point: 6.365°, 2.418° (the coordinates the reanalysis values are taken for)
Dataset version: era5-1991-2020-scores1.1
Last processed: 1 August 2026

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.