Chicago Weather in July
July is the hottest and one of the sunniest months for Chicago, Illinois. Most days have temperatures in the 80s degrees Fahrenheit (over 26 degrees Celsius). And two-thirds of daylight hours are sunny.
This page gives detailed information on the typical July temperature, precipitation, sun, humidity, wind and storms for Chicago. The numbers here are historical averages based on temperature, rain and snow measurements gathered at Chicago Midway Airport and other climate data from Chicago O'Hare International Airport.
Temperature
85 °F | July average high | 30 °C |
68 °F | July average low | 20 °C |
July is Chicago's hottest month overall, with temperatures peaking from the 9th to 17th. That is when the daily high averages 86 °F (30 °C) and nighttime lows are 68 °F (20 °C).
24 days | 80 °F max. or more (27 °C) |
21 days | 70 °F min. or less (21 °C) |
Usually every day in July warms to over 70 °F (21 °C) in Chicago. The city averages 8 days this month when the thermometer reaches into the 90s °F (over 32 °C). A day with the temperature as hot as 100 °F (38 °C) or above occurs every few years in July.
The thermometer dips to 60 °F (16 °C) or below on 3 nights. But July does not normally get as cold as 50 °F (10 °C).
Rain
4.0 in | total precipitation | 102 mm |
10 days | of rain |
Half the time, Chicago receives 2.3 to 4.5 inches (58 to 115 mm) of rainfall in July. One in four years has drier weather, while another one in four is wetter.
Sun
66 % | sunshine |
8 days | clear skies |
The sun's rays reach the ground in Chicago during 66 percent of daylight hours on average in July, for a total of 304 hours in the month. Typically on 8 days this month the sky is mainly clear, with at most 30 percent cloud cover.
Sunlight in July at Chicago lasts for 14 hours and 51 minutes a day on average. The longest day of the month is the 1st with 15 hours and 10 minutes of daylight. By the end of the month, the days have shortened to 14:26 from sunrise to sunset. These durations can vary by a minute or two from year to year.
Humidity
69 % | July average humidity |
The relative humidity in Chicago during July usually peaks at 82 percent in the morning then drops to 54 percent by mid afternoon.
Local Time | 12 am | 3 am | 6 am | 9 am | 12 pm | 3 pm | 6 pm | 9 pm |
Humidity % | 79 | 82 | 82 | 66 | 57 | 54 | 58 | 71 |
Wind
8.4 mph | July wind speed average | 13.5 kph |
July is one of the least windy months in Chicago.
Storms
3 days | rainfall of 0.5 inches (13 mm) or more |
6 days | with thunderstorms in July |
July gets more thunderstorms than most months.
Reference
The weather data here are long-term averages provided by the US National Centers for Environmental Information (NCEI). Temperature and precipitation are 1991-2020 normals while humidity and thunderstorms are 1961-1990 normals.