July weather forecastWilliamson, IL
July
Weather in July
July, like June, in Williamson, Illinois, is another warm summer month, with an average temperature fluctuating between 67.5°F (19.7°C) and 84.2°F (29°C).Temperature
In Williamson, July is the warmest month, with temperatures averaging a high of 84.2°F (29°C) and a low of 67.5°F (19.7°C).Heat index
For most parts of July, the heat index is computed to be a torrid 95°F (35°C). Special measures are necessary to avoid heat cramps and heat exhaustion. Persistent activity could result in heatstroke.Understanding the heat index involves considering values for shaded locales with light wind. Uninterrupted exposure to the sun may boost the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is a calculated temperature value of how hot it feels when the moisture in the air is factored in. One's perception of temperature can vary depending on physical activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. In the direct sunlight, the weather's impact can be amplified, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are largely significant for babies and toddlers. Children often fail to recognize the requirement to rest and rehydrate. Thirst, being a late symptom of dehydration, underlines the importance of maintaining hydration, especially during ongoing physical activities.
The human body cools itself through perspiration, as excessive warmth is removed from the body through sweat evaporation. In circumstances of high air temperature and humidity (high heat index), the body's perspiration is restricted, heightening the feeling of warmth. With body temperatures on the rise, inefficient heat shedding can lead to dehydration and its associated complications.
Humidity
July is the most humid month in Williamson, with an average relative humidity of 81%.Rainfall
In Williamson, in July, it is raining for 14 days, with typically 1.5" (38mm) of accumulated precipitation. In Williamson, during the entire year, the rain falls for 121.4 days and collects up to 14.72" (374mm) of precipitation.Snowfall
In Williamson, snow does not fall in April through October.Daylight
In Williamson, the average length of the day in July is 14h and 35min.On the first day of July, sunrise is at 5:37 am and sunset at 8:28 pm. On the last day of the month, sunrise is at 5:59 am and sunset at 8:11 pm CDT.
Sunshine
The months with the most sunshine are June and July, with an average of 10.3h of sunshine.UV index
The months with the highest UV index are June through August, with an average maximum UV index of 6. A UV Index value of 6 to 7 symbolizes a high health risk from exposure to the Sun's UV rays for ordinary individuals.Note: The maximum daily UV index of 6 during July translates into the following directions:
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. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in July
Williamson, IL
- Average high temperature in July: 84.2°F
The warmest month (with the highest average high temperature) is July (84.2°F).
The month with the lowest average high temperature is January (35.6°F).
- Average low temperature in July: 67.5°F
The month with the highest average low temperature is July (67.5°F).
The coldest month (with the lowest average low temperature) is January (22.6°F).
Average pressure in July
Williamson, 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 (29.92"Hg).
Average wind speed in July
Williamson, IL
- Average wind speed in July: 5.8mph
The windiest month (with the highest average wind speed) is January (10mph).
The calmest month (with the lowest average wind speed) is July (5.8mph).
Average humidity in July
Williamson, IL
- Average humidity in July: 81%
The month with the highest relative humidity is July (81%).
The month with the lowest relative humidity is October (71%).
Average rainfall in July
Williamson, IL
- Average rainfall in July: 1.5"
The wettest month (with the highest rainfall) is June (1.89").
The driest month (with the least rainfall) is February (0.67").
Average rainfall days in July
Williamson, IL
- Average rainfall days in July: 14 days
The month with the highest number of rainy days is July (14 days).
The month with the least rainy days is January (5.8 days).
Average snowfall in July
Williamson, IL
- Average snowfall in July: 0"
The month with the highest snowfall is December (0.98").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in July
Williamson, IL
- Average snowfall days in July: 0 days
The month with the highest number of snowfall days is January (6.3 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in July /
Average sunshine in July
Williamson, IL
- Average daylight in July: 14h and 36min
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 30min).
- Average sunshine in July: 10h and 18min
The months with the most sunshine are June and July (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in July
Williamson, IL
- Average sunshine days in July: 12.5 days
The month with the most sunshine days is January (20.9 days).
The month with the least sunshine days is July (12.5 days).
Average UV index in July
Williamson, IL
- Average UV index in July: 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 July
Williamson, IL
- Average cloud cover in July: 29
The month with the most cloud cover is January (Cloud cover 52).
The months with the least cloud cover are June, July, August and September (Cloud cover 29).
Average visibility in July
Williamson, 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).
