In
July, the weather in
Saint Louis reaches its most varied. The city sees its highest levels of rainfall, with an average of 40mm (1.57") collected over 4 days. July also marks the peak of high temperatures averaging 30.7°C (87.3°F), while nights turn noticeably warmer with temperatures maintained at a steady 24.4°C (75.9°F). The relative humidity escalates to 78.5%, and the sea water warms up to a pleasant 26.3°C (79.3°F). Although the weather can be unpredictable this month, the extended daylight hours and warm sea temperatures still allow for a memorable visit.
Temperature
July brings an average high-temperature of a still tropical 30.7°C (87.3°F), nearly identical to the preceding month. In July, Saint Louis records an average nighttime temperature of 24.4°C (75.9°F).
Heat index
July's heat index is computed to be a sweltering 39°C (102.2°F). Implement heightened safety measures - risk of heat exhaustion and heat cramps is increased. Prolonged activity may result in heatstroke.
It is crucial to understand that heat index figures are for shade and gentle wind conditions. Direct exposure to sunshine could lead to a heat index increase by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', offers an insight into how hot it feels when we factor in moisture content. Metabolic differences, pregnancy status, and the level of physical activity are additional factors influencing an individual's weather perception. Be mindful that being in direct sunlight might mean feeling hotter, with the heat index rising by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values remain especially vital for babies and toddlers. Children often fail to recognize the requirement to rest and rehydrate. Thirst, being a late symptom of dehydration, underlines the importance of maintaining hydration, especially during ongoing physical activities.
Evaporating sweat, an outcome of perspiration, is key in assisting the human body to moderate its temperature. An elevated level of relative humidity hinders evaporation, leading to decreased heat elimination from the body, inducing a sensation of excess heat. When heat gain surpasses the level the body can shed, body temperature begins to increase, and consequently, overheating and dehydration can occur, with varying severity.
Humidity
The average relative humidity in July is 78.5%.
Rainfall
In July, in Saint Louis, the rain falls for 4 days. Throughout July, 40mm (1.57") of precipitation is accumulated. Throughout the year, there are 20 rainfall days, and 261mm (10.28") of precipitation is accumulated.
Sea temperature
In Saint Louis, in July, the average water temperature is 26.3°C (79.3°F).
Note: Temperatures between 25°C (77°F) and 29°C (84.2°F) are ideal for swimming, diving, and similar water activities, ensuring pleasure and comfort for extended periods without feeling uneasy.
Daylight
In Saint Louis, the average length of the day in July is 12h and 58min.
On the first day of the month, sunrise is at 06:37 and sunset at 19:41. On the last day of July, sunrise is at 06:47 and sunset at 19:37 GMT.
Sunshine
The average sunshine in July in Saint Louis is 7.9h.
UV index
The months with the highest UV index are
March through
September, with an average maximum UV index of 12. A UV Index reading of 11, and higher, represents an ultimate health vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.
Note: In July, the maximum UV index of 12 transforms into these recommendations:
Execute all vital precautions. Preventing sun damage is of utmost importance. Make an effort to avoid direct sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation, and note that objects like parasols or canopies might not offer full sun protection. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses. Broad-spectrum sunscreen with an SPF of 30 or above should be applied generously and reapplied every two hours and right after any outdoor activity or swim. Alert! UV radiation becomes sharper due to reflections from sand and water.