August weather forecastRiver Forest, IL
August
Weather in August
The last month of the summer, August, is also a moderately hot month in River Forest, Illinois, with an average temperature ranging between max 79.3°F (26.3°C) and min 66.7°F (19.3°C).Temperature
August's arrival brings an average high-temperature of a still warm 79.3°F (26.3°C), slightly deviating from July's 79.7°F (26.5°C). River Forest experiences an average temperature drop to a refreshing 66.7°F (19.3°C) during August nights.Humidity
In River Forest, the average relative humidity in August is 74%.Rainfall
In River Forest, in August, it is raining for 16.4 days, with typically 3.5" (89mm) of accumulated precipitation. In River Forest, during the entire year, the rain falls for 157.8 days and collects up to 33.7" (856mm) of precipitation.Snowfall
In River Forest, snow does not fall in June through September.Daylight
In River Forest, the average length of the day in August is 13h and 49min.On the first day of the month, sunrise is at 5:45 am and sunset at 8:09 pm. On the last day of August, in River Forest, sunrise is at 6:16 am and sunset at 7:25 pm CDT.
Sunshine
The month with the most sunshine is August, with an average of 10.6h of sunshine.UV index
The months with the highest UV index are June through August, with an average maximum UV index of 6. A UV Index value of 6 to 7 symbolizes a high health hazard from unsafe exposure to UV radiation for average individuals.Note: In August, a daily UV index of 6 turns into the following recommendations:
Skirt overexposure. People with light complexions might get scorched in under 20 minutes. Remember that UV radiation from the Sun is strongest between 10 a.m. and 4 p.m. Make an effort to limit direct sun exposure during this time. Stay sun-safe with clothing that is both closely woven and worn loosely.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
River Forest, IL
- Average high temperature in August: 79.3°F
The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is January (28.9°F).
- Average low temperature in August: 66.7°F
The month with the highest average low temperature is July (67.5°F).
The coldest month (with the lowest average low temperature) is January (19.4°F).
Average pressure in August
River Forest, 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
River Forest, IL
- Average wind speed in August: 7mph
The windiest month (with the highest average wind speed) is January (11.1mph).
The calmest months (with the lowest average wind speed) are July and August (7mph).
Average humidity in August
River Forest, IL
- Average humidity in August: 74%
The month with the highest relative humidity is January (82%).
The month with the lowest relative humidity is October (72%).
Average rainfall in August
River Forest, IL
- Average rainfall in August: 3.5"
The wettest month (with the highest rainfall) is May (4.49").
The driest month (with the least rainfall) is December (1.57").
Average rainfall days in August
River Forest, IL
- Average rainfall days in August: 16.4 days
The month with the highest number of rainy days is May (18.8 days).
The month with the least rainy days is February (5.1 days).
Average snowfall in August
River Forest, IL
- Average snowfall in August: 0"
The month with the highest snowfall is February (4.69").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in August
River Forest, IL
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (10.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in August /
Average sunshine in August
River Forest, 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 36min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in August
River Forest, IL
- Average sunshine days in August: 11.8 days
The month with the most sunshine days is December (16.7 days).
The month with the least sunshine days is July (9.9 days).
Average UV index in August
River Forest, IL
- Average UV index in August: 6
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in August
River Forest, IL
- Average cloud cover in August: 27
The month with the most cloud cover is January (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in August
River Forest, 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).
