July weather forecastDetroit, IL
July
Weather in July
July, like June, in Detroit, Illinois, is a moderately hot summer month, with an average temperature fluctuating between 66.7°F (19.3°C) and 84.4°F (29.1°C).Temperature
With its high average temperature of 84.4°F (29.1°C) and a low of 66.7°F (19.3°C), July is regarded as the warmest month.Heat index
During July, the heat index is calculated to be a torrid 95°F (35°C). More preventive actions are needed, risk of heat exhaustion and heat cramps is significant. Prolonged activity may trigger heatstroke.In reference to the heat index, it's for places in shade and with a slight wind. Direct sunlight might cause an increase of up to 15 Fahrenheit (8 Celsius) degrees in the heat index.
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. This effect tends to be personal, with the weather perception differing among individuals due to variations in body mass, height, and exertion. 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 are particularly relevant to babies and toddlers. Young ones often disregard the necessity to rest and hydrate. Thirst usually indicates advanced dehydration - hence, it is key to stay hydrated, particularly during ongoing physical activities.
The primary way humans combat excessive warmth is by perspiring, letting sweat evaporate and cool the body. When relative humidity is at high levels, the evaporation rate lessens, causing the body to keep more heat than it would in less humid conditions. When heat surpasses the body's release mechanisms, dehydration and overheating risks become pronounced.
Humidity
June and July, with an average relative humidity of 81%, are the most humid months.Rainfall
In July, in Detroit, Illinois, the rain falls for 13.5 days. Throughout July, 1.69" (43mm) of precipitation is accumulated. In Detroit, during the entire year, the rain falls for 128.8 days and collects up to 18.35" (466mm) of precipitation.Snowfall
In Detroit, snow does not fall in May through October.Daylight
In July, the average length of the day is 14h and 38min.On the first day of July, sunrise is at 5:39 am and sunset at 8:34 pm. On the last day of the month, sunrise is at 6:01 am and sunset at 8:16 pm CDT.
Sunshine
The months with the most sunshine are June and July, with an average of 10.3h of sunshine.UV index
June through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index reading of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV radiation for average individuals.Note: A daily maximum UV index of 6 in July translates into the following instructions:
Persist with precautions and heed sun safety advice. Prevention of sunburn is compulsory. Limit your direct sun exposure, especially between 10 a.m. and 4 p.m., when UV radiation is strongest. Shade structures might not provide complete sun protection. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in July
Detroit, IL
- Average high temperature in July: 84.4°F
The warmest month (with the highest average high temperature) is July (84.4°F).
The month with the lowest average high temperature is January (33.8°F).
- Average low temperature in July: 66.7°F
The month with the highest average low temperature is July (66.7°F).
The coldest month (with the lowest average low temperature) is January (21.6°F).
Average pressure in July
Detroit, IL
- Average pressure in July: 29.96"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in July
Detroit, IL
- Average wind speed in July: 6mph
The windiest months (with the highest average wind speed) are January, February and April (9.8mph).
The calmest month (with the lowest average wind speed) is July (6mph).
Average humidity in July
Detroit, IL
- Average humidity in July: 81%
The months with the highest relative humidity are June and July (81%).
The month with the lowest relative humidity is October (71%).
Average rainfall in July
Detroit, IL
- Average rainfall in July: 1.69"
The wettest month (with the highest rainfall) is May (2.44").
The driest month (with the least rainfall) is February (0.75").
Average rainfall days in July
Detroit, IL
- Average rainfall days in July: 13.5 days
The month with the highest number of rainy days is May (16.8 days).
The month with the least rainy days is January (4.5 days).
Average snowfall in July
Detroit, IL
- Average snowfall in July: 0"
The month with the highest snowfall is January (2.05").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in July
Detroit, 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
Detroit, 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 24min).
- 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
Detroit, IL
- Average sunshine days in July: 13.7 days
The month with the most sunshine days is December (20.7 days).
The month with the least sunshine days is June (12.3 days).
Average UV index in July
Detroit, 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
Detroit, 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
Detroit, 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).





