Contents
- Weather in August
- Frequently asked questions
- Average temperature in August
- Average pressure in August
- Average wind speed in August
- Average humidity in August
- Average rainfall in August
- Average rainfall days in August
- Average snowfall in August
- Average snowfall days in August
- Average daylight in August
- Average sunshine in August
- Average sunshine days in August
- Average UV index in August
- Average cloud cover in August
- Average visibility in August
Weather in August
Temperature
August brings an average high-temperature of a still warm 81.7°F (27.6°C), showing a slight difference from July's 82.8°F (28.2°C). Dennison experiences an average low-temperature reading of 64°F (17.8°C) throughout August.Heat index
The heat index for August is computed to be a hot 87.8°F (31°C). Enduring exposure and ongoing activity could cause a sense of fatigue and subsequent heat cramps.Given the heat index, its values are aligned with shaded sites and gentle winds. Exposure to direct sunlight may make the heat index values climb by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', is found by incorporating humidity levels into the air temperature measurement. Factors including metabolic differences, physical activity, and clothing are additional elements that influence the individual's temperature experience. When in direct sunlight, one should be cautious as it can raise the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for babies and toddlers. Younglings are generally more in peril than adults due to their reduced perspiration. Coupled with a larger skin surface relative to their tiny bodies and greater heat production because of their activity, they become more at risk.
Humidity
In Dennison, the average relative humidity in August is 81%.Rainfall
In Dennison, Illinois, in August, it is raining for 14.6 days, with typically 2.56" (65mm) of accumulated precipitation. In Dennison, during the entire year, the rain falls for 159.3 days and collects up to 34.41" (874mm) of precipitation.Snowfall
In Dennison, Illinois, snow does not fall in May through October.Daylight
The average length of the day in August is 13h and 40min.On the first day of August, sunrise is at 5:50 am and sunset at 8:02 pm. On the last day of the month, sunrise is at 6:18 am and sunset at 7:22 pm CDT.
Sunshine
In Dennison, the average sunshine in August is 9.1h.UV index
June through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index of 6 to 7 symbolizes a high health hazard from exposure to the Sun's UV rays for the average person.Note: The maximum daily UV index of 6 in August interprets into the following recommendations:
Steer clear of overexposure. Fair-skinned individuals can be scorched in less than 20 minutes. Seek shade and limit direct sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Keep in mind that shade structures like parasols or canopies do not offer complete sun protection. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are August temperatures?
What is the average humidity in August?
How much does it rain in August?
When it does not snow?
What is the average length of the day in August in Dennison?
When are sunrise and sunset in August in Dennison?
How many hours of sunshine does Dennison have in August?
What are the months with the highest UV index?
How high is the UV index in August?
Average temperature in August
Dennison, IL
- Average high temperature in August: 81.7°F
The warmest month (with the highest average high temperature) is July (82.8°F).
The month with the lowest average high temperature is January (34.3°F).
- Average low temperature in August: 64°F
The month with the highest average low temperature is July (65.8°F).
The coldest month (with the lowest average low temperature) is January (22.3°F).
Average pressure in August
Dennison, IL
- Average pressure in August: 29.99"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in August
Dennison, IL
- Average wind speed in August: 6mph
The windiest month (with the highest average wind speed) is February (10.1mph).
The calmest months (with the lowest average wind speed) are July and August (6mph).
Average humidity in August
Dennison, IL
- Average humidity in August: 81%
The month with the highest relative humidity is July (82%).
The month with the lowest relative humidity is October (72%).
Average rainfall in August
Dennison, IL
- Average rainfall in August: 2.56"
The wettest month (with the highest rainfall) is April (4.96").
The driest month (with the least rainfall) is September (1.81").
Average rainfall days in August
Dennison, IL
- Average rainfall days in August: 14.6 days
The month with the highest number of rainy days is May (20.6 days).
The month with the least rainy days is January (8.2 days).
Average snowfall in August
Dennison, IL
- Average snowfall in August: 0"
The month with the highest snowfall is January (2.56").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in August
Dennison, IL
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (7.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in August /
Average sunshine in August
Dennison, IL
- Average daylight in August: 13h and 4min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in August: 9h and 1min
The month with the most sunshine is June (Average sunshine: 10h and 12min).
The months with the least sunshine are January and December (Average sunshine: 4h and 18min).
Average sunshine days in August
Dennison, IL
- Average sunshine days in August: 13.5 days
The month with the most sunshine days is November (18.4 days).
The month with the least sunshine days is May (7.9 days).
Average UV index in August
Dennison, 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, February, October, November and December (UV index 2).
Average cloud cover in August
Dennison, IL
- Average cloud cover in August: 32
The month with the most cloud cover is January (Cloud cover 57).
The months with the least cloud cover are June, August and September (Cloud cover 32).
Average visibility in August
Dennison, IL
- Average visibility in August: 5mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
Dennison, Illinois, USA
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