August weather forecast
Chesterfield, MO

After the peak of July, August continues to carry forward the chorus of summer, albeit with slightly less intensity. It remains primarily hot in the city with a temperature transition from the high of July to a slightly milder 86.2°F (30.1°C). The city gears up to get back to routine as summer vacations come to a close and school bells begin to signal the upcoming academic year. Despite the ongoing heat, the anticipation of autumn’s arrival subtly starts to surface. With the end of summer on the horizon, the residents of Chesterfield maximize their moments under the summer sun.

Temperature

The dawn of August sees an average high-temperature of a still hot 86.2°F (30.1°C), subtly contrasting with July's 87.4°F (30.8°C). The average temperature during August nights dips to an enjoyable 66.9°F (19.4°C).

Heat index

For most parts of August, the heat index is estimated at a fiery hot 96.8°F (36°C). Incorporate additional preventive steps, heat exhaustion and heat cramps are possible. Long-lasting activity may cause heatstroke.
Given the heat index, its values are aligned with shaded sites and gentle winds. A rise of up to 15 Fahrenheit (8 Celsius) degrees in the heat index could result from direct sunlight.
Note: The heat index, also known as 'feels like' or 'felt air temperature', gives a temperature feeling by integrating air temperature and humidity. The perception of temperature can be subjective, varying based on activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. It is noteworthy that being in direct sunlight can enhance the weather's impact, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. In general, younger individuals are at greater risk than adults because they tend to sweat less. Also, having a larger skin surface to body size ratio and greater heat production due to their active behavior contribute to this danger.
Humans rely on perspiration as a cooling mechanism, wherein the evaporating sweat counteracts excessive warmth. During conditions of high air temperature and humidity (high heat index), the body's ability to perspire is inhibited, increasing the sensation of warmth. Rising body temperatures due to excess heat retention could signify impending heat disorders.

Humidity

The average relative humidity in August in Chesterfield is 74%.

Rainfall

In August, the rain falls for 14.5 days. Throughout August, 2.99" (76mm) of precipitation is accumulated. Throughout the year, in Chesterfield, there are 139.6 rainfall days, and 26.1" (663mm) of precipitation is accumulated.

Snowfall

In Chesterfield, snow does not fall in April through October.

Daylight

In Chesterfield, the average length of the day in August is 13h and 38min.
On the first day of the month, sunrise is at 6:04 am and sunset at 8:12 pm. On the last day of August, sunrise is at 6:31 am and sunset at 7:33 pm CDT.

Sunshine

The average sunshine in August is 10.3h.

UV index

In August, the average daily maximum UV index in Chesterfield is 6. A UV Index estimate of 6 to 7 represents a high health vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.
Note: In August, the maximum UV index of 6 translates into these guidelines:
Shield from overexposure. Defense against sun-related harm is required. Be aware that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. and try to reduce direct sun exposure during this period as much as possible. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.