Cotonou, Benin Climate & Monthly Averages
Cotonou has a tropical wet-and-dry climate. March is the hottest month, averaging 87° by day; August is the coldest at 80°.
Rain, not cold, divides the year in Cotonou
Temperature barely moves in Cotonou - 3°C between the average March and the average August. Rainfall does the work instead: 8.6 inches (219 mm) in June against 19 mm (0.7 in) in December.
The wet-and-dry rhythm at a glance
Average highs hold at or above 30°C for 5 months of the year, December through April being the unbroken run. August sits at the other end of the year: 80°F (26°C) by day, 75°F (24°C) at night. March is the warm end of the year, averaging 87°F (30°C) by day and 81°F (27°C) overnight.
The gridded 2015-2024 daily record for this location tops out at 96°F (35°C) and bottoms at 69°F (21°C) - decade extremes, not all-time station records. Relative humidity averages 83% across the year, more humid than 94% of the 3496 cities in our dataset - enough that summer afternoons feel hotter than the thermometer says, which is what the dew point converter is for.
Sunshine averages 9.7 hours a day over the year, peaking in December at 10.5 hours. 2 months average under 20 mm of rain, the longest unbroken stretch running December through January.
More climate facts for Cotonou
- Hottest month: March - highs near 87°F (30°C)
- Coldest month: August - highs near 80°F (26°C)
- Decade extremes (2015-2024): 96°F (35°C) high · 69°F (21°C) low
- Wettest month: June (25 rainy days) · Sunniest: December (10.5 h sun/day)
- Climate type: tropical wet-and-dry
- Annual swing: 3°C between the average warmest and coolest month · day to night: 3°C
- Months averaging 30°C or hotter: 5
- Average humidity: 83%
Choosing the right part of the year in Cotonou
Choose dates by rain, not just temperature
December to February and August is the sweet spot for Cotonou - humidity and rainfall are at their lowest, which is what actually varies here. Expect 85°F (29°C) in the afternoon and around 9 days of rain in a typical month of it. For the same question asked the other way round, see where else is warm in December.
What the humidity changes
Pack for Cotonou with light clothing for the warm months, proper waterproofs rather than an umbrella - wet days are the norm here and moisture-wicking fabrics for the humidity. Even in March, lows of 81°F (27°C) make an extra layer worth the space.
Warm all year: the monthly rain pattern
Each card shows the average high and low. The bar places that month between Cotonou's coldest night and warmest afternoon.
January
- Rain
- 5 days
- Sunshine
- 10.3 h
- Daylight
- 11.8 h
February
- Rain
- 8 days
- Sunshine
- 10.4 h
- Daylight
- 11.9 h
March
- Rain
- 15 days
- Sunshine
- 9.8 h
- Daylight
- 12.1 h
April
- Rain
- 15 days
- Sunshine
- 9.9 h
- Daylight
- 12.3 h
May
- Rain
- 21 days
- Sunshine
- 9.7 h
- Daylight
- 12.4 h
June
- Rain
- 25 days
- Sunshine
- 8.3 h
- Daylight
- 12.5 h
July
- Rain
- 18 days
- Sunshine
- 9.4 h
- Daylight
- 12.5 h
August
- Rain
- 15 days
- Sunshine
- 9.6 h
- Daylight
- 12.3 h
September
- Rain
- 22 days
- Sunshine
- 8.9 h
- Daylight
- 12.1 h
October
- Rain
- 24 days
- Sunshine
- 9.3 h
- Daylight
- 12.0 h
November
- Rain
- 19 days
- Sunshine
- 10.4 h
- Daylight
- 11.8 h
December
- Rain
- 7 days
- Sunshine
- 10.5 h
- Daylight
- 11.8 h
Looking for warmer alternatives? Browse warm places by month, or compare Cotonou's coolest part of the year: August, July, September.
Monthly temperature and rain table
| Month | High | Low | Rain days | Precipitation | Sunshine | Daylight | Wet-day chance | Humidity |
|---|---|---|---|---|---|---|---|---|
| January | 87° | 77° | 5 | 0.8 in | 10.3 h/day | 11.8 h | 17% | 79% |
| February | 87° | 79° | 8 | 1.3 in | 10.4 h/day | 11.9 h | 28% | 81% |
| March | 87° | 81° | 15 | 2.8 in | 9.8 h/day | 12.1 h | 47% | 82% |
| April | 87° | 81° | 15 | 2.7 in | 9.9 h/day | 12.3 h | 50% | 81% |
| May | 85° | 80° | 21 | 5.9 in | 9.7 h/day | 12.4 h | 66% | 82% |
| June | 82° | 77° | 25 | 8.6 in | 8.3 h/day | 12.5 h | 83% | 85% |
| July | 80° | 76° | 18 | 4.4 in | 9.4 h/day | 12.5 h | 58% | 86% |
| August | 80° | 75° | 15 | 3.0 in | 9.6 h/day | 12.3 h | 49% | 86% |
| September | 81° | 76° | 22 | 5.0 in | 8.9 h/day | 12.1 h | 74% | 86% |
| October | 83° | 77° | 24 | 6.0 in | 9.3 h/day | 12.0 h | 76% | 85% |
| November | 85° | 79° | 19 | 2.6 in | 10.4 h/day | 11.8 h | 64% | 83% |
| December | 87° | 78° | 7 | 0.7 in | 10.5 h/day | 11.8 h | 24% | 79% |
How Cotonou compares for rain and warmth
- Afternoons run 3°C above the following night - a flatter daily curve than almost every other city we track.
- Cotonou averages 81°F (27°C) across the year - warmer than 95% of the 3496 cities we track.
- Its warmest and coolest months are 3°C apart - a steadier year than all but 10% of the 3496 cities we track.
These comparisons use the same ten-year window for every city in the dataset.
How the calendar changes in warm-weather Cotonou
March through May
Through March through May, Cotonou sits firmly in the heat: 86°F (30°C) by day, 80°F (27°C) after dark, and rain falls on around 50 of the 90 days.
June through August
Through June through August, Cotonou runs hot: 81°F (27°C) by day, 76°F (25°C) after dark, and rain falls on around 58 of the 90 days.
September through November
Through September through November, Cotonou sits firmly in the heat: 83°F (28°C) by day, 78°F (25°C) after dark, and rain falls on around 65 of the 90 days.
December through February
Through December through February, Cotonou sits firmly in the heat: 87°F (30°C) by day, 78°F (26°C) after dark, and expect showers on roughly 21 days across the season. Daylight is generous - around 10.4 hours of sun a day.
Questions about heat and rain in Cotonou
How hot does Cotonou get in summer?
How sunny is Cotonou?
When is the dry season in Cotonou?
How much does the weather change through the year in Cotonou?
Cotonou temperature extremes in the 2015–2024 dataset
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ. Need another precipitation unit? Use the rainfall converter.