May weather forecast
Cotonou, Benin

May brings a gradual decline in high temperatures in Cotonou, while the rainfall reaches its yearly zenith. The increase in precipitation, which results in 197mm (7.76") of rainfall, verifies May as the month with the highest rainfall. Interestingly, the city's long daylight duration of 12.4 hours assists in maintaining an elevated UV index of 12 units. The city experiences minor fluctuations in temperature levels and a small decrease in sea temperature compared to the previous month. This month, combined with its high levels of humidity, certainly conveys a highly tropical climate to its residents and tourists.

Temperature

Cotonou's weather in May indicates an average high-temperature of a still hot 31°C (87.8°F), nearly consistent with the 31.6°C (88.9°F) of April. Throughout May, Cotonou's nights cool down to an average of 24.6°C (76.3°F).

Heat index

May's average heat index is calculated to be a blisteringly hot 41°C (105.8°F). Undertake extra safety actions, heat cramps and heat exhaustion are expected. Heatstroke may result from lengthy activity.
Data suggests that the heat index is set for environments in shade and with a light wind. The heat index could experience an increase of 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'feels like' or 'real feel', is a fusion of air temperature and moisture levels to demonstrate the sensation of heat. Elements such as metabolic variations, pregnancy, and physical exertion can shape one's weather perception. Awareness of direct sun exposure is crucial as it has the potential to heighten the weather's effects, pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to children. Young ones often ignore the need to take a break and drink fluids. Thirst is a late-stage symptom of dehydration - hence, maintaining hydration, particularly during extended physical activities, is crucial.
The process of perspiration is vital for the human body to get rid of excess warmth by allowing sweat to evaporate. With higher relative humidity, the rate of evaporation is reduced, resulting in increased heat retention in the body compared to drier air. When the heat gained surpasses the body's cooling capacity, temperatures rise, signaling potential health concerns.

Humidity

In May, the average relative humidity is 80%.

Rainfall

In May, the rain falls for 11 days. Throughout May, 197mm (7.76") of precipitation is accumulated. In Cotonou, during the entire year, the rain falls for 75 days and collects up to 1308mm (51.5") of precipitation.

Sea temperature

The months with the warmest seawater are March through May and November, with an average sea temperature of 29°C (84.2°F).
Note: In water temperatures ranging between 25°C (77°F) and 29°C (84.2°F), activities such as swimming and diving become highly pleasurable for long durations.

Daylight

In May, the average length of the day is 12h and 25min.
On the first day of the month, sunrise is at 06:36 and sunset at 18:58. On the last day of May, sunrise is at 06:34 and sunset at 19:02 WAT.

Sunshine

The average sunshine in May in Cotonou is 6.9h.

UV index

The months with the highest UV index are February through May, August through October, with an average maximum UV index of 12. A UV Index value of 11, and more, symbolizes an ultimate health vulnerability from unprotected exposure to Sun's UV rays for average individuals.
Note: The average daily UV index of 12 in May transforms into the following instructions:
Employ every precaution of importance, unprotected skin and eyes could burn within moments. Stay out of direct sunlight and seek shade between 10 a.m. and 4 p.m., when UV radiation is strongest, but remember that shade devices may not offer full sun protection. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears. Even if the day is cloudy, sunscreen with SPF of at least 30 should be applied generously and reapplied often, particularly after swimming or outdoor exercise. Warning! The reflection of sand and water increases the UV dose.