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 onset of August brings an average high-temperature of a warm 85.5°F (29.7°C), nearly matching the July temperature. O'Fallon observes an average low-temperature of 66.6°F (19.2°C) during August.Heat index
The heat index in August is appraised at a fiery hot 95°F (35°C). Emphasize additional safety, risk of heat cramps and heat exhaustion is high. Continuous activity might result in heatstroke.Heat index specifics point out values are for conditions of shade and a slight breeze. Heat index values can rise by 15 Fahrenheit (8 Celsius) degrees when in direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'real feel', is an aggregate value of air's warmth and moisture to show the human-felt temperature. Additional elements encompassing metabolic differences, the degree of physical activity, and attire can impact the individual's perception of temperature. Being under direct sunshine can magnify the heat experience, possibly pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical to babies and toddlers. Young ones regularly neglect the requirement for rest and fluid replenishment. Thirst is a late stage of dehydration - so, it is necessary to keep hydrated, particularly during extended periods of physical exertion.
The human body normally cools itself by perspiration. Excessive warmth is eliminated from the body by evaporation of sweat. In situations of high air temperature combined with high humidity (significant heat index), the body's ability to perspire is reduced, heightening the sense of warmth. Rising body temperatures resulting from an imbalance in heat absorption can lead to potential thermal issues.
Humidity
The average relative humidity in August is 75%.Rainfall
In O'Fallon, during August, the rain falls for 12.8 days and regularly aggregates up to 2.48" (63mm) of precipitation. In O'Fallon, Missouri, during the entire year, the rain falls for 132.3 days and collects up to 21.06" (535mm) of precipitation.Snowfall
April through October are months without snowfall.Daylight
In August, the average length of the day is 13h and 38min.On the first day of the month, sunrise is at 6:04 am and sunset at 8:13 pm. On the last day of August, sunrise is at 6:31 am and sunset at 7:34 pm CDT.
Sunshine
In O'Fallon, the average sunshine in August is 10.2h.UV index
The months with the highest UV index are May through August, with an average maximum UV index of 6. A UV Index of 6 to 7 symbolizes a high health vulnerability from exposure to the Sun's UV rays for ordinary individuals.Note: In August, the maximum UV index of 6 suggests this advice:
Elude overexposure. Fair-skinned people could get burnt in less than 20 minutes. Try to minimize direct Sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Also note that objects like parasols or canopies might not provide complete sun protection. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot does it get in August?
What is the average humidity in August?
How much does it rain in O'Fallon in August?
When it does not snow?
What is the average length of the day in August?
What time are sunrise and sunset in August?
How many hours of sunshine does O'Fallon have in August?
What is the month with the highest UV index?
How high is the UV index in August?
Average temperature in August
O'Fallon, MO
- Average high temperature in August: 85.5°F
The warmest month (with the highest average high temperature) is July (87.1°F).
The month with the lowest average high temperature is January (37.4°F).
- Average low temperature in August: 66.6°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (23.7°F).
Average pressure in August
O'Fallon, MO
- Average pressure in August: 29.97"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in August
O'Fallon, MO
- Average wind speed in August: 5.6mph
The windiest month (with the highest average wind speed) is January (9.1mph).
The calmest month (with the lowest average wind speed) is July (5.5mph).
Average humidity in August
O'Fallon, MO
- Average humidity in August: 75%
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (70%).
Average rainfall in August
O'Fallon, MO
- Average rainfall in August: 2.48"
The wettest month (with the highest rainfall) is May (2.76").
The driest month (with the least rainfall) is December (0.91").
Average rainfall days in August
O'Fallon, MO
- Average rainfall days in August: 12.8 days
The month with the highest number of rainy days is May (15.7 days).
The month with the least rainy days is February (6.8 days).
Average snowfall in August
O'Fallon, MO
- Average snowfall in August: 0"
The month with the highest snowfall is February (1.61").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in August
O'Fallon, MO
- Average snowfall days in August: 0 days
The months with the highest number of snowfall days are January and February (5.8 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
O'Fallon, MO
- 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 month with the most sunshine is June (Average sunshine: 10h and 30min).
The months with the least sunshine are January and February (Average sunshine: 4h and 42min).
Average sunshine days in August
O'Fallon, MO
- Average sunshine days in August: 14.7 days
The month with the most sunshine days is December (20.6 days).
The month with the least sunshine days is July (12.6 days).
Average UV index in August
O'Fallon, MO
- 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, MO
- Average cloud cover in August: 28
The month with the most cloud cover is January (Cloud cover 50).
The months with the least cloud cover are June, July, August and September (Cloud cover 28).
Average visibility in August
O'Fallon, MO
- 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, Missouri, USA
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