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
O'Fallon's average high-temperature in August sits at a moderately hot 85.5°F (29.7°C), showing little difference from the previous month. In the month of August, an average of 66.6°F (19.2°C) marks the low-temperature in O'Fallon.Heat index
Throughout August, the heat index is evaluated at a very hot 95°F (35°C). Incorporate additional preventive steps, heat exhaustion and heat cramps are possible. Long-lasting activity may cause heatstroke.Always consider that heat index estimations are for light winds and places in the shade. Exposure to the direct sun could elevate the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', gives a temperature feeling by integrating air temperature and humidity. This effect is personal, influenced by the individual's physical activity and heat sensitivity, shaped by factors including wind, attire, and metabolic variations. 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 particularly relevant to babies and toddlers. Children frequently underestimate the importance of resting and drinking fluids. Thirst is a symptom of advanced dehydration - hence the need to hydrate regularly, especially during protracted physical exercises.
Evaporation of sweat is the main factor behind the cooling effect of perspiration in the human body. Excessive relative humidity disturbs the body's typical cooling process by reducing evaporation, leading to a decrease in body cooling rate and an increase in the sensation of warmth. When body temperature rises due to an imbalance in heat gain, there's a potential for dehydration and overheating.
Humidity
In August, the average relative humidity in O'Fallon is 75%.Rainfall
In O'Fallon, Missouri, in August, it is raining for 12.8 days, with typically 2.48" (63mm) of accumulated precipitation. In O'Fallon, during the entire year, the rain falls for 132.3 days and collects up to 21.06" (535mm) of precipitation.Snowfall
In O'Fallon, snow does not fall in April through October.Daylight
In O'Fallon, the average length of the day in August is 13h and 38min.On the first day of August in O'Fallon, sunrise is at 6:04 am and sunset at 8:13 pm. On the last day of the month, sunrise is at 6:31 am and sunset at 7:34 pm CDT.
Sunshine
The average sunshine in August is 10.2h.UV index
May through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health risk from exposure to the Sun's UV rays for the average person.Note: The daily high UV index of 6 during August translates into the following recommendations:
Ward off overexposure. Defence against solar harm is crucial. The Sun emits the most powerful UV radiation between 10 a.m. and 4 p.m. Try to avoid direct sunlight during this period. Stay sun-safe with clothing that is both closely woven and worn loosely.
Frequently asked questions
How hot does it get in O'Fallon in August?
What is the average humidity in August in O'Fallon?
How many days does it rain in August in O'Fallon?
When it does not snow in O'Fallon?
How many hours of daylight does O'Fallon have in August?
When are sunrise and sunset in August in O'Fallon?
How many hours of sunshine does O'Fallon have in August?
What is the month with the highest UV index in O'Fallon?
What is the UV index reading in August in O'Fallon?
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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