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
The arrival of August brings an average high-temperature of a still moderately hot 81.1°F (27.3°C), subtly diverging from July's 81.5°F (27.5°C). McLean in August anticipates an average nighttime temperature of 63.5°F (17.5°C).Heat index
For August, the heat index is calculated to be a hot 87.8°F (31°C). With extended exposure and activity, one might feel exhausted and experience heat cramps.One should be cognizant that the heat index values are tailored for shaded spots and mild winds. The heat index values could be amplified by up to 15 Fahrenheit (8 Celsius) degrees in direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'real feel', gives an indication of how one might feel in terms of heat after considering humidity. Additional elements including metabolic differences, the level of physical activity, and attire have a role in shaping the individual's temperature perception. Awareness of direct sun exposure is crucial as it has the potential to heighten the weather's effects, pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for babies and toddlers. Young ones often underestimate the need for rest and rehydration. Thirst appears late in dehydration - hence, it is important to keep hydrated, particularly during prolonged physical activities.
Humidity
The average relative humidity in August is 82%.Rainfall
In McLean, Illinois, during August, the rain falls for 13.3 days and regularly aggregates up to 1.65" (42mm) of precipitation. Throughout the year, in McLean, there are 135 rainfall days, and 17.72" (450mm) of precipitation is accumulated.Snowfall
May through October are months without snowfall.Daylight
In August, the average length of the day is 13h and 43min.On the first day of the month, sunrise is at 5:55 am and sunset at 8:10 pm. On the last day of August, in McLean, Illinois, sunrise is at 6:23 am and sunset at 7:29 pm CDT.
Sunshine
In McLean, the average sunshine in August is 9.8h.UV index
June through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index value of 6 to 7 symbolizes a high health hazard from unprotected exposure to Sun's UV rays for ordinary individuals.Note: A maximum UV index of 6 in August translates into the following recommendations:
Stick with precautions and abide by sun safety procedures. Evading sunburn is essential. The Sun's UV radiation is most potent between the hours of 10 a.m. and 4 p.m. Try to avoid direct sunlight during this time. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average August temperature in McLean?
What is the average humidity in August in McLean?
How many days does it rain in August in McLean?
When it does not snow in McLean?
How many hours of daylight does McLean have in August?
When are sunrise and sunset in August in McLean?
How many hours of sunshine does McLean have in August?
What is the month with the highest UV index in McLean?
What is the UV index reading in August in McLean?
Average temperature in August
McLean, IL
- Average high temperature in August: 81.1°F
The warmest month (with the highest average high temperature) is July (81.5°F).
The month with the lowest average high temperature is January (31.6°F).
- Average low temperature in August: 63.5°F
The month with the highest average low temperature is July (65.1°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).
Average pressure in August
McLean, IL
- Average pressure in August: 29.98"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in August
McLean, IL
- Average wind speed in August: 6.3mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.3mph).
Average humidity in August
McLean, IL
- Average humidity in August: 82%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (70%).
Average rainfall in August
McLean, IL
- Average rainfall in August: 1.65"
The wettest month (with the highest rainfall) is May (2.2").
The driest month (with the least rainfall) is December (0.87").
Average rainfall days in August
McLean, IL
- Average rainfall days in August: 13.3 days
The month with the highest number of rainy days is May (16.5 days).
The month with the least rainy days is February (5.9 days).
Average snowfall in August
McLean, IL
- Average snowfall in August: 0"
The month with the highest snowfall is January (2.2").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in August
McLean, IL
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (9.5 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
McLean, IL
- Average daylight in August: 13h and 4min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in August: 9h and 5min
The month with the most sunshine is June (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in August
McLean, IL
- Average sunshine days in August: 14.3 days
The months with the most sunshine days are November and December (20 days).
The month with the least sunshine days is May (11.6 days).
Average UV index in August
McLean, 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, November and December (UV index 2).
Average cloud cover in August
McLean, IL
- Average cloud cover in August: 31
The month with the most cloud cover is January (Cloud cover 57).
The month with the least cloud cover is September (Cloud cover 30).
Average visibility in August
McLean, 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).
McLean, Illinois, USA
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