Contents
- Weather in July
- Frequently asked questions
- Average temperature in July
- Average pressure in July
- Average wind speed in July
- Average humidity in July
- Average rainfall in July
- Average rainfall days in July
- Average snowfall in July
- Average snowfall days in July
- Average daylight in July
- Average sunshine in July
- Average sunshine days in July
- Average UV index in July
- Average cloud cover in July
- Average visibility in July
Weather in July
Temperature
July stands out as O'Fallon's warmest month, with temperatures ranging between an average high of 85.6°F (29.8°C) and a low of 68.2°F (20.1°C).Heat index
July's average heat index is calculated to be a very hot 98.6°F (37°C). Implement enhanced safety actions, heat cramps and heat exhaustion could occur. Sustained activity might result in heatstroke.Research indicates the heat index considers values in shaded locales and with light winds. The heat index might be elevated by 15 Fahrenheit (8 Celsius) degrees due to direct sun exposure.
Note: The heat index, also known as 'real feel' or 'apparent temperature', quantifies the warmth felt when relative humidity is considered. This effect tends to be personal, with the weather perception differing among individuals due to variations in body mass, height, and exertion. Keep in mind that direct sunshine exposure can amplify the weather's effects, possibly increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical for babies and toddlers. Younglings are generally more in peril than adults due to their reduced perspiration. Coupled with a larger skin surface relative to their tiny bodies and greater heat production because of their activity, they become more at risk.
Evaporating sweat, thanks to perspiration, acts as a natural air conditioner for the human body. With a high level of moisture in the air, the evaporation process becomes less efficient, preventing the body from cooling down efficiently and resulting in a sensation of overheating. Overheating and dehydration threats arise when heat gain goes beyond what the body can comfortably shed.
Humidity
The months with the highest humidity in O'Fallon are May, July and August, with an average relative humidity of 79%.Rainfall
July is the month with the most rainfall. Rain falls for 13.1 days and accumulates 1.42" (36mm) of precipitation.Snowfall
April through October are months without snowfall in O'Fallon.Daylight
The average length of the day in July in O'Fallon is 14h and 33min.On the first day of July in O'Fallon, sunrise is at 5:39 am and sunset at 8:28 pm. On the last day of the month, sunrise is at 6:01 am and sunset at 8:10 pm CDT.
Sunshine
The months with the most sunshine are June and July, with an average of 10.4h of sunshine.UV index
The months with the highest UV index in O'Fallon are May through August, with an average maximum UV index of 6. A UV Index reading of 6 to 7 represents a high health risk from exposure to the Sun's UV rays for the ordinary person.Note: The maximum UV index of 6 during July translates into these guidelines:
Evade overexposure. Individuals with fair skin risk burning in under 20 minutes. Minimize exposure to direct sunlight and seek shade from 10 a.m. to 4 p.m., when UV radiation is most intense, but remember that shade structures may not offer complete protection. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key.
Frequently asked questions
What month is the hottest in O'Fallon?
Is it hot in O'Fallon during July?
What is the most humid month in O'Fallon?
What is the average humidity in July in O'Fallon?
What is the wettest month in O'Fallon?
How much does it rain in O'Fallon in July?
When it does not snow in O'Fallon?
How many hours of daylight does O'Fallon have in July?
When are sunrise and sunset in July in O'Fallon?
What are the months with the most sunshine in O'Fallon?
How long on average sun shines in July in O'Fallon?
What are the months with the highest UV index in O'Fallon?
How high is the UV index in July in O'Fallon?
Average temperature in July
O'Fallon, IL
- Average high temperature in July: 85.6°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 July: 68.2°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 July
O'Fallon, IL
- Average pressure in July: 29.97"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in July
O'Fallon, IL
- Average wind speed in July: 5.6mph
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 July
O'Fallon, IL
- Average humidity in July: 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 July
O'Fallon, IL
- Average rainfall in July: 1.42"
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 July
O'Fallon, IL
- Average rainfall days in July: 13.1 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 July
O'Fallon, IL
- Average snowfall in July: 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 July
O'Fallon, IL
- Average snowfall days in July: 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 July /
Average sunshine in July
O'Fallon, IL
- Average daylight in July: 14h and 3min
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 July: 10h and 2min
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 July
O'Fallon, IL
- Average sunshine days in July: 15.5 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 July
O'Fallon, IL
- Average UV index in July: 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 July
O'Fallon, IL
- Average cloud cover in July: 29
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 July
O'Fallon, IL
- Average visibility in July: 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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