The onset of the rainy season defines
May, with a significant upturn in humidity and a remarkable increase in rainfall reaching 71mm (2.8"). Temperatures remain steady with
April, but the nights become warmer. Concurrently, daylight time peaks, matching the longest days of the year. Even with the increased clouds and rain, sunshine hours remain surprisingly steady. The city's weather, at this point, has completely transitioned from the dry season.
Temperature
The commencement of May in
Ouagadougou brings an average high-temperature of a still fiery hot 37.3°C (99.1°F), marking an inconsequential divergence from April. Nighttime temperatures consistently average a moderately hot 25.5°C (77.9°F) during May.
Heat index
The average heat index in May is appraised at a life-threatening hot 48°C (118.4°F).
Attention: Heat exhaustion and heat cramps are quite likely. Heatstroke becomes a risk with continued exertion.
Factoring in the heat index, values are geared towards shaded areas with light breezes. When under direct sunshine, the heat index may be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', combines both the air temperature and the humidity level to give a perceived human temperature. Factors encompassing physical activity, clothing, and metabolic differences have a role in shaping the individual's impression of temperature. It is essential to realize that direct sunlight can escalate the perceived temperature, increasing the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. Children often overlook the need for breaks and fluid intake. Thirst is a late-stage sign of dehydration - hence, it is necessary to stay hydrated, especially during extended periods of physical activities.
The process of perspiration is vital for the human body to get rid of excess warmth by allowing sweat to evaporate. With high air temperature and humidity (high heat index) conditions, sweat production is restricted, leading to an amplified perception of heat. Overheating and potential dehydration arise when body heat gain eclipses its release capability.
Humidity
In May, the average relative humidity is 52.5%.
Rainfall
In Ouagadougou, in May, it is raining for 3.3 days, with typically 71mm (2.8") of accumulated precipitation. In Ouagadougou, during the entire year, the rain falls for 35.2 days and collects up to 788mm (31.02") of precipitation.
Daylight
In May, the average length of the day is 12h and 42min.
On the first day of the month, sunrise is at 05:45 and sunset at 18:20. On the last day of May, sunrise is at 05:39 and sunset at 18:27 GMT.
Sunshine
January through
March, May,
October and
November, with an average of 9h of sunshine, are months with the most sunshine.
UV index
February through
September, with an average maximum UV index of 12, are months with the highest UV index. A UV Index estimate of 11, and higher, represents an ultimate health vulnerability from unsafe exposure to UV radiation for ordinary individuals.
Note: The maximum UV index of 12 during May leads to these instructions:
Take every essential safety procedure. Individuals with fair skin could sustain burns in less than 5 minutes. The time between 10 a.m. and 4 p.m. is when UV radiation is at its peak. Limit exposure to direct sunlight during these hours. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance. A broad-spectrum sunscreen of SPF 30+ should be liberally applied and re-applied every two hours, and immediately after an outdoor workout or a swim.