August weather forecastDowners Grove, IL
August
Weather in August
August offers somewhat of a reprieve in Downers Grove from July's potent warmth. The decline in peak temperature by 1.3°F (-17.1°C) indicates a move towards cooler seasons. The relative humidity remains steady, a sign that the season's fiery touch is softening. Despite being a summer month, August welcomes rainfall, though at a lesser rate than July. The persistent sunshine may dwindle slightly but still dominates the days, adding a charming edge to the weather as Downers Grove prepares for a shift in season.Temperature
Downers Grove signifies an average high-temperature of a still warm 81.1°F (27.3°C) in August, closely mirroring the 82.4°F (28°C) of July. In August, Downers Grove records an average nighttime temperature of 64.8°F (18.2°C).Heat index
August's heat index is computed to be a hot 86°F (30°C). Unrelenting activity during exposure could cause fatigue and potentially lead to heat cramps.Understanding the heat index involves considering values for shaded locales with light wind. The heat index can potentially augment by 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', takes into account both air temperature and humidity to illustrate what people actually feel. Elements such as metabolic variations, pregnancy, and physical exertion can influence one'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 are particularly relevant to children. Typically, children face more danger than adults as they usually perspire less. Their larger skin surface relative to their small bodies and increased heat output from their activities enhance their risk.
Humidity
In Downers Grove, the average relative humidity in August is 75%.Rainfall
In Downers Grove, in August, it is raining for 12.2 days, with typically 1.34" (34mm) of accumulated precipitation. Throughout the year, there are 118.5 rainfall days, and 13.74" (349mm) of precipitation is accumulated.Snowfall
In Downers Grove, snow does not fall in May through September.Daylight
In August, the average length of the day is 13h and 49min.On the first day of the month, sunrise is at 5:46 am and sunset at 8:09 pm. On the last day of August, sunrise is at 6:17 am and sunset at 7:26 pm CDT.
Sunshine
August has the most sunshine of the year, with an average of 10h of sunshine.UV index
June through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV radiation for the average person.Note: A daily maximum UV index of 6 in August translates into the following instructions:
Prevent overexposure. Protection from the sun's harmful effects is needed. The Sun emits the most powerful UV radiation between 10 a.m. and 4 p.m. Try to avoid direct sunlight during this period. Employ a wide-brim hat for potent defense against up to 50% of UV rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Downers Grove, IL
- Average high temperature in August: 81.1°F
The warmest month (with the highest average high temperature) is July (82.4°F).
The month with the lowest average high temperature is January (28.8°F).
- Average low temperature in August: 64.8°F
The month with the highest average low temperature is July (66.4°F).
The coldest month (with the lowest average low temperature) is January (17.1°F).
Average pressure in August
Downers Grove, IL
- Average pressure in August: 29.98"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in August
Downers Grove, IL
- Average wind speed in August: 6.1mph
The windiest month (with the highest average wind speed) is January (9.7mph).
The calmest month (with the lowest average wind speed) is August (6.1mph).
Average humidity in August
Downers Grove, IL
- Average humidity in August: 75%
The months with the highest relative humidity are January and February (82%).
The month with the lowest relative humidity is October (72%).
Average rainfall in August
Downers Grove, IL
- Average rainfall in August: 1.34"
The wettest month (with the highest rainfall) is May (1.97").
The driest month (with the least rainfall) is December (0.63").
Average rainfall days in August
Downers Grove, IL
- Average rainfall days in August: 12.2 days
The month with the highest number of rainy days is May (14.9 days).
The month with the least rainy days is February (4.2 days).
Average snowfall in August
Downers Grove, IL
- Average snowfall in August: 0"
The month with the highest snowfall is February (2.28").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in August
Downers Grove, IL
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (9.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in August /
Average sunshine in August
Downers Grove, IL
- Average daylight in August: 13h and 48min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in August: 10h and 0min
The month with the most sunshine is August (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in August
Downers Grove, IL
- Average sunshine days in August: 14.8 days
The month with the most sunshine days is December (20.7 days).
The month with the least sunshine days is July (11.8 days).
Average UV index in August
Downers Grove, IL
- Average UV index in August: 6
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in August
Downers Grove, IL
- Average cloud cover in August: 31
The month with the most cloud cover is January (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in August
Downers Grove, 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).
