When to Visit Cotonou

Cotonou sits on a narrow strip of land wedged between the Atlantic Ocean and Lake Nokoue. That geography shapes everything about how the weather works here. The city doesn't follow the familiar four-season calendar. Instead, it runs on two wet seasons and two dry seasons stacked through the year. Temperatures stay so consistent month to month that the thermometer rarely tells you which season you're in. What changes is the sky. Clear and carrying a faint harmattan haze in the dry months. Heavy and overcast when the rains take hold. The long rainy season commands attention. It builds from March onward. Peaks emphatically in June when Cotonou regularly receives more rainfall in a single month than London sees in three. Then eases through July before a short lull arrives in August. September and October bring a second, shorter wet season. The city then settles into the long dry spell from November through February. During those dry months, the harmattan occasionally pushes south from the Sahara. Not with the full force it carries inland. But enough to leave the air carrying a faint dustiness. The horizon turns milky at the edges. Temperatures across all twelve months are notably stable. They hover between 28°C (82°F) and 32°C (90°F) regardless of season. The Atlantic breeze keeps Cotonou a degree or two cooler than inland Benin. The city's lowest temperatures tend to come in July and August. Cloud cover from the rainy season moderates the heat then. Humidity sits consistently around 70 percent year-round. Not oppressive by regional standards. But enough that a first-time visitor will feel it the moment they step outside.