December weather forecast
Cotonou, Benin

Capping off the calendar year, December in Cotonou mirrors many of the same climates found in November, yet with an even further reduction in rainfall. A noteworthy characteristic of the final month is a significant decrease of total rainfall, down to 20mm (0.79"), marking it as the driest month of the year. The daylight duration remains constant at 11.8 hours, with slightly less sunshine duration than November of around 7.2 hours. Both air and sea temperatures are kept relatively stable during this month, perfectly aligning with the festive season. The UV index drops to 10 units, drawing the year to a close on a milder note.

Temperature

With December's advent, Cotonou sees an average high-temperature of a still hot 30.8°C (87.4°F), subtly shifted from November's 30.9°C (87.6°F). Throughout December, the nighttime temperature averages to a moderately hot 23.8°C (74.8°F).

Heat index

Throughout December, the heat index is calculated to be a scorching 41°C (105.8°F). Implement heightened safety measures - risk of heat exhaustion and heat cramps is increased. Prolonged activity may result in heatstroke.
One should consider that heat index numbers are for shaded settings and light wind. Heat index values can rise by 15 Fahrenheit (8 Celsius) degrees when in direct sunlight.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is calculated by taking the relative humidity value for a specific location and factoring it into the air temperature reading. A person's impression of weather can be affected by numerous aspects, among them metabolic variations, pregnancy, and activity levels. It is essential to be conscious of the fact that direct sunlight can intensify the felt heat, leading to an elevation in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical for babies and toddlers. Children frequently underestimate the necessity to rest and hydrate. Thirst is a late sign of dehydration - thus, it is vital to stay hydrated, particularly during lengthy physical exercises.
To cool down, the human body relies on perspiration, a process where excessive heat is eliminated as sweat evaporates. With a lot of moisture in the air, the evaporation process is not as effective, and the body does not cool down as efficiently, creating a perception of overheating. Heat disorders may be on the horizon when body temperatures rise from inadequate heat management.

Humidity

In December, the average relative humidity is 81%.

Rainfall

In Cotonou, in December, it is raining for 2 days, with typically 20mm (0.79") of accumulated precipitation. In Cotonou, during the entire year, the rain falls for 75 days and collects up to 1308mm (51.5") of precipitation.

Sea temperature

In Cotonou, the average seawater temperature in December is 28°C (82.4°F).
Note: Between the temperatures of 25°C (77°F) and 29°C (84.2°F), water is considered very warm, providing pleasure in water activities without discomfort over lengthy periods.

Daylight

With an average of 11h and 48min of daylight, December has the shortest days of the year.
On the first day of the month, sunrise is at 06:46 and sunset at 18:33. On the last day of December, sunrise is at 07:00 and sunset at 18:46 WAT.

Sunshine

In December, the average sunshine is 7.2h.

UV index

The month with the lowest UV index is December, with an average maximum UV index of 10. A UV Index reading of 8 to 10 represents a very high health risk from unprotected exposure to Sun's UV rays for the ordinary person.
Note: In December, the maximum UV index of 10 transforms into these recommendations:
Take the necessary steps to protect yourself; unprotected skin and eyes are vulnerable to damage. Seek shade and limit direct Sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its peak, but be aware that not all shade structures provide complete sun protection. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key. Apply liberally and reapply a broad-spectrum sunscreen of SPF 30+ every two hours, and promptly after any outdoor workout or a swim. Stay alert! Reflective properties of sand and water amplify the Sun's UV radiation.