May signals the actual arrival of
Saint Louis's wet season, with average high temperatures lingering around 30.3°C (86.5°F). This coincides with the beginning of a palpable increase in humidity to 69.5% and the sea temperature rising to an inviting 21.8°C (71.2°F). The month is characterized by its negligible rainfall, with there being virtually no rainy days this month. Despite the high humidity, the pleasant sea temperature and extended daylight hours offer a perfect balance, making beach visits and water sports quite appealing. This novel blend of weather conditions makes the city's vibrant and historic sights all the more enjoyable to explore throughout the month.
Temperature
May, marked by an average high-temperature of 30.3°C (86.5°F) and a low-temperature of 19.4°C (66.9°F), is the coldest month.
Heat index
In May, the average heat index is computed to be a very hot 36°C (96.8°F). Extra precautions are necessary, heat cramps and heat exhaustion are plausible outcomes. Extended activity could lead to heatstroke.
Factoring in the heat index, values are geared towards shaded areas with light breezes. The heat index could see an increase by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'real feel' or 'apparent temperature', is an index that combines air temperature and relative humidity to determine the human-perceived temperature equivalent. This effect tends to be personal, with the weather perception differing among individuals due to variations in body mass, height, and exertion. Direct exposure to sun rays can potentially augment the heat sensation, elevating the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. Children frequently do not understand the need for recuperation and hydration. Thirst, being a late manifestation of dehydration, underlines the need to hydrate frequently, especially when engaging in prolonged physical exercises.
In response to overheating, the human body perspires to cool down, mainly through the evaporation of sweat. In circumstances of high air temperature and humidity (high heat index), the body's perspiration is restricted, heightening the feeling of warmth. Accumulating heat beyond the body's cooling measures leads to rising temperatures and potential ailments.
Humidity
The average relative humidity in May in Saint Louis is 69.5%.
Rainfall
Months with rainfall in Saint Louis are
January through
March, May through
December. May is the first month it rains. Throughout May, Saint Louis receives 0mm (0") of precipitation. Throughout the year, 261mm (10.28") of rain is accumulated.
Sea temperature
In Saint Louis,
Senegal, in May, the average water temperature is 21.8°C (71.2°F).
Note: Swimming in 21.8°C (71.2°F) is not a pleasurable activity for the majority of people. Breathing becomes increasingly challenging as water temperature descends from 21°C (69.8°F) to 15°C (59°F).
Daylight
In Saint Louis, the average length of the day in May is 12h and 53min.
On the first day of May in Saint Louis, Senegal, sunrise is at 06:41 and sunset at 19:24. On the last day of the month, sunrise is at 06:33 and sunset at 19:34 GMT.
Sunshine
In May, the average sunshine in Saint Louis is 9.1h.
UV index
March through
September, with an average maximum UV index of 12, are months with the highest UV index in Saint Louis. A UV Index estimate of 11, and higher, represents an extreme threat to health from exposure to the Sun's UV rays for ordinary individuals.
Note: The daily maximum UV index of 12 in May interprets into the following advice:
Implement every essential safety step. Individuals with fair skin might receive burns in less than 5 minutes. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat. Regardless of cloud cover, it's recommended to apply generously and reapply often a sunscreen with an SPF of at least 30, especially after swimming or any outdoor activity. Take warning! Reflective sand and water surfaces intensify the Sun's UV rays.