August weather forecastChester, IL
August
Weather in August
The last month of the summer, August, is also a moderately hot month in Chester, Illinois, with an average temperature fluctuating between 66.2°F (19°C) and 85.8°F (29.9°C).Temperature
Chester records an average high-temperature of a warm 85.8°F (29.9°C) in August, closely mirroring the climate of the previous month. Chester, in the month of August, anticipates a consistent average low-temperature of 66.2°F (19°C).Heat index
August's average heat index is appraised at a sweltering 98.6°F (37°C). Adopt additional preventive measures, heat cramps and heat exhaustion are potential outcomes. Prolonged activity may trigger heatstroke.Evaluating the heat index requires understanding its values in the shade and with gentle winds. Heat index values may rise by up to 15 Fahrenheit (8 Celsius) degrees when exposed to direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'real feel', embodies the combination of air temperature and moisture content to illustrate perceived heat. Metabolic differences, pregnancy status, and the level of physical activity are additional factors influencing an individual's weather perception. With direct sunlight, be aware that it might enhance the heat sensation, raising the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical to babies and toddlers. Children often miss understanding the importance of rest and rehydration. Thirst usually appears late during dehydration - therefore, maintaining hydration, particularly during long physical activities, is essential.
The human body normally cools itself by perspiration. Excessive warmth is eliminated from the body by evaporation of sweat. Augmented relative humidity impedes typical body cooling mechanisms by lowering the evaporation rate, resulting in decreased body cooling and an amplified perception of heat. If heat absorption exceeds the body's cooling ability, body temperature can elevate, resulting in potential thermal illnesses.
Humidity
The average relative humidity in August is 77%.Rainfall
In Chester, during August, the rain falls for 14.9 days and regularly aggregates up to 3.19" (81mm) of precipitation. In Chester, during the entire year, the rain falls for 156.4 days and collects up to 34.25" (870mm) of precipitation.Snowfall
In Chester, snow does not fall in May through September.Daylight
The average length of the day in August is 13h and 35min.On the first day of the month, sunrise is at 6:03 am and sunset at 8:07 pm. On the last day of August, sunrise is at 6:29 am and sunset at 7:29 pm CDT.
Sunshine
In August, the average sunshine is 10.2h.UV index
The months with the highest UV index are May through August, with an average maximum UV index of 6. A UV Index estimate of 6 to 7 represents a high health hazard from unsafe exposure to UV radiation for the average person.Note: The UV index of 6 in August translates into these instructions:
Act on precautions and pay attention to sun safety recommendations. Avoidance of sunburn is obligatory. Stay in the shade and avoid direct Sun exposure from 10 a.m. to 4 p.m., a period when UV radiation is particularly strong, noting that parasols or canopies may not offer total sun protection. Employ a hat with a wide brim for robust protection, cutting UV exposure by half.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Chester, IL
- Average high temperature in August: 85.8°F
The warmest month (with the highest average high temperature) is July (87.4°F).
The month with the lowest average high temperature is January (39.6°F).
- Average low temperature in August: 66.2°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (25.7°F).
Average pressure in August
Chester, IL
- Average pressure in August: 29.98"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in August
Chester, IL
- Average wind speed in August: 5.5mph
The windiest month (with the highest average wind speed) is January (9.4mph).
The calmest month (with the lowest average wind speed) is August (5.5mph).
Average humidity in August
Chester, IL
- Average humidity in August: 77%
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall in August
Chester, IL
- Average rainfall in August: 3.19"
The wettest month (with the highest rainfall) is April (4.13").
The driest month (with the least rainfall) is September (1.97").
Average rainfall days in August
Chester, IL
- Average rainfall days in August: 14.9 days
The month with the highest number of rainy days is July (17.8 days).
The month with the least rainy days is January (7.9 days).
Average snowfall in August
Chester, IL
- Average snowfall in August: 0"
The month with the highest snowfall is February (2.56").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in August
Chester, IL
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is February (5.2 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in August /
Average sunshine in August
Chester, IL
- Average daylight in August: 13h and 36min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in August: 10h and 12min
The months with the most sunshine are June and July (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in August
Chester, IL
- Average sunshine days in August: 13 days
The month with the most sunshine days is October (18.9 days).
The month with the least sunshine days is July (9.8 days).
Average UV index in August
Chester, IL
- Average UV index in August: 6
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in August
Chester, IL
- Average cloud cover in August: 28
The months with the most cloud cover are January and February (Cloud cover 48).
The month with the least cloud cover is June (Cloud cover 27).
Average visibility in August
Chester, IL
- Average visibility in August: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
