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
In August, the average high-temperature registers at a still moderately hot 81.5°F (27.5°C), nearly identical to July's 82.2°F (27.9°C). The month of August records an average low-temperature of 64°F (17.8°C) in Sullivan.Heat index
August's heat index is evaluated at a tropical 87.8°F (31°C). Continued exposure and engagement in activity might trigger tiredness and subsequently heat cramps.One should consider that heat index numbers are for shaded settings and light wind. Facing direct sunlight may hike up the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', joins air temperature with relative humidity to produce a temperature perception for humans. Elements of metabolic variation, physical activity, and clothing contribute to the effect of temperature on an individual. When directly under the sun, the weather's impact can intensify, possibly boosting the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially vital to children. Youths are typically more endangered than adults since they usually sweat less. Their larger skin surface concerning their smaller bodies and higher heat production due to activity further adds to their vulnerability.
Humidity
The average relative humidity in August in Sullivan, Illinois, is 82%.Rainfall
In Sullivan, during August, the rain falls for 13 days and regularly aggregates up to 1.54" (39mm) of precipitation. Throughout the year, in Sullivan, there are 130.9 rainfall days, and 15.43" (392mm) of precipitation is accumulated.Snowfall
In Sullivan, snow does not fall in May through October.Daylight
In Sullivan, the average length of the day in August is 13h and 41min.On the first day of August in Sullivan, sunrise is at 5:54 am and sunset at 8:06 pm. On the last day of the month, sunrise is at 6:22 am and sunset at 7:26 pm CDT.
Sunshine
In Sullivan, Illinois, the average sunshine in August is 9.8h.UV index
The months with the highest UV index are June through August, with an average maximum UV index of 6. A UV Index estimate of 6 to 7 represents a high health vulnerability from unsafe exposure to UV radiation for average individuals.Note: The maximum daily UV index, 6 in August, converts into the following recommendations:
Stand by precautions and apply sun safety measures. Evading sunburn is of great importance. It's important to stay in the shade and limit exposure to the sun from 10 a.m. to 4 p.m., when UV radiation is most intense, although remember that shade structures may not provide full sun protection. Outfit yourself in sun-safe attire, like long sleeves, pants, a hat, and UV-blocking sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the temperature in August in Sullivan?
What is the average humidity in August in Sullivan?
How much does it rain in Sullivan in August?
When it does not snow in Sullivan?
How many hours of daylight does Sullivan have in August?
When are sunrise and sunset in August in Sullivan?
How many hours of sunshine does Sullivan have in August?
What is the month with the highest UV index in Sullivan?
What is the UV index reading in August in Sullivan?
Average temperature in August
Sullivan, IL
- Average high temperature in August: 81.5°F
The warmest month (with the highest average high temperature) is July (82.2°F).
The month with the lowest average high temperature is January (33.6°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 (21.6°F).
Average pressure in August
Sullivan, IL
- Average pressure in August: 29.98"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
Sullivan, IL
- Average wind speed in August: 6.3mph
The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest months (with the lowest average wind speed) are July and August (6.3mph).
Average humidity in August
Sullivan, IL
- Average humidity in August: 82%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (70%).
Average rainfall in August
Sullivan, IL
- Average rainfall in August: 1.54"
The wettest month (with the highest rainfall) is June (1.85").
The driest month (with the least rainfall) is February (0.71").
Average rainfall days in August
Sullivan, IL
- Average rainfall days in August: 13 days
The month with the highest number of rainy days is May (16.3 days).
The month with the least rainy days is February (5.9 days).
Average snowfall in August
Sullivan, IL
- Average snowfall in August: 0"
The month with the highest snowfall is January (1.54").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in August
Sullivan, IL
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (6.4 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
Sullivan, 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 5min
The month with the most sunshine is June (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in August
Sullivan, IL
- Average sunshine days in August: 15.6 days
The month with the most sunshine days is October (20.5 days).
The month with the least sunshine days is May (12.3 days).
Average UV index in August
Sullivan, 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
Sullivan, IL
- Average cloud cover in August: 31
The month with the most cloud cover is January (Cloud cover 56).
The month with the least cloud cover is June (Cloud cover 30).
Average visibility in August
Sullivan, 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).
Sullivan, Illinois, USA
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