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 shift into August uncovers an average high-temperature of a still moderately hot 84.2°F (29°C), subtly different from the previous month. In the month of August, an average of 66°F (18.9°C) marks the low-temperature.Heat index
August's heat index is calculated to be a very hot 95°F (35°C). Adopt special protective actions against heat exhaustion and heat cramps. Long-duration activity risks heatstroke.When assessing, remember that heat index measurements are for light winds and shaded spots. Heat index values have the potential to be boosted by 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'real feel', is a calculation that merges air temperature and relative humidity to depict the sensation of warmth. The influence of weather is personal, with a diverse population experiencing it differently due to differences in body mass, stature, and degree of activity. Exposure to direct sun rays can influence the heat you feel, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular importance for children. Young children are more at risk than adults since they tend to sweat less. Moreover, their large skin surface in proportion to their small bodies and the high heat production due to their activities contribute to their vulnerability.
The human body normally cools itself by perspiration. Excessive warmth is eliminated from the body by evaporation of sweat. Elevated relative humidity diminishes evaporation, thereby reducing the body's ability to shed heat and creating a feeling of being too warm. Excessive heat that's not properly managed leads to increased body temperatures and resultant health issues.
Humidity
The months with the highest humidity in O'Fallon are May, July and August, with an average relative humidity of 79%.Rainfall
In O'Fallon, in August, during 11.1 rainfall days, 1.26" (32mm) of precipitation is typically accumulated. In O'Fallon, during the entire year, the rain falls for 108.8 days and collects up to 10.24" (260mm) of precipitation.Snowfall
In O'Fallon, snow does not fall in April through October.Daylight
The average length of the day in August is 13h and 37min.On the first day of the month, sunrise is at 6:02 am and sunset at 8:09 pm. On the last day of August, in O'Fallon, sunrise is at 6:28 am and sunset at 7:30 pm CDT.
Sunshine
In August, the average sunshine in O'Fallon, Illinois, is 10.2h.UV index
May through August, with an average maximum UV index of 6, are months with the highest UV index in O'Fallon. A UV Index estimate of 6 to 7 represents a high health vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: The maximum UV index, 6 during August, leads to the following recommendations:
Elude overexposure. Fair-skinned people could get burnt in less than 20 minutes. Limit direct sun exposure and seek shade between 10 a.m. and 4 p.m., the time of the most intense UV radiation, noting that shade structures may not provide total sun protection. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.
Frequently asked questions
How hot is it in O'Fallon in August?
What are the most humid months in O'Fallon?
What is the average humidity in August in O'Fallon?
How much does it rain in O'Fallon in August?
When it does not snow in O'Fallon?
What is the average length of the day in August in O'Fallon?
What time are sunrise and sunset in August in O'Fallon?
How long on average sun shines in August in O'Fallon?
What is the month with the highest UV index in O'Fallon?
How high is the UV index in August in O'Fallon?
Average temperature in August
O'Fallon, IL
- Average high temperature in August: 84.2°F
The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (37.8°F).
- Average low temperature in August: 66°F
The month with the highest average low temperature is July (68.2°F).
The coldest month (with the lowest average low temperature) is January (24.6°F).
Average pressure in August
O'Fallon, IL
- Average pressure in August: 29.98"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in August
O'Fallon, IL
- Average wind speed in August: 5.7mph
The windiest month (with the highest average wind speed) is January (9.5mph).
The calmest month (with the lowest average wind speed) is July (5.6mph).
Average humidity in August
O'Fallon, IL
- Average humidity in August: 79%
The months with the highest relative humidity are May, July and August (79%).
The month with the lowest relative humidity is October (70%).
Average rainfall in August
O'Fallon, IL
- Average rainfall in August: 1.26"
The wettest month (with the highest rainfall) is July (1.42").
The driest month (with the least rainfall) is December (0.31").
Average rainfall days in August
O'Fallon, IL
- Average rainfall days in August: 11.1 days
The month with the highest number of rainy days is July (13.1 days).
The month with the least rainy days is December (4.6 days).
Average snowfall in August
O'Fallon, IL
- Average snowfall in August: 0"
The month with the highest snowfall is January (0.51").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in August
O'Fallon, IL
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (4.7 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
O'Fallon, IL
- Average daylight in August: 13h and 4min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in August: 10h and 1min
The months with the most sunshine are June and July (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 30min).
Average sunshine days in August
O'Fallon, IL
- Average sunshine days in August: 18 days
The month with the most sunshine days is December (23.6 days).
The months with the least sunshine days are May and July (15.5 days).
Average UV index in August
O'Fallon, IL
- Average UV index in August: 6
The months with the highest UV index are May, 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
O'Fallon, IL
- Average cloud cover in August: 28
The month with the most cloud cover is January (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in August
O'Fallon, 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).
O'Fallon, Illinois, USA
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