Average Temperatures for Illinois in July





Average temperatures for July at cities throughout Illinois are listed below.

You can jump to a separate table for each region of the state: Chicago Area, Northern Illinois, Central Illinois and Southern Illinois.

The tables give the normal maximum and minimum temperatures based on weather data collected from 1991 to 2020 by the US National Centers for Environmental Information.

Chicago Area

Average July temperatures
High °F Low °F Place High °C Low °C
84 65 Aurora 29 18
84 63 Chicago Botanical Garden 29 17
85 68 Chicago Midway Airport 30 20
85 66 Chicago O'Hare Airport 29 19
84 63 Elgin 29 17
84 64 Joliet 29 18
82 61 Rochelle 28 16

Northern Illinois

Average temperatures in July
High °F Low °F Place High °C Low °C
82 64 Antioch 28 18
83 63 DeKalb 28 17
83 64 Dixon 28 18
82 62 Freeport 28 17
86 65 Moline 30 18
84 64 Rockford 29 18
81 62 Waukegan 27 17

Central Illinois

Normal temperatures for July
High °F Low °F Place High °C Low °C
87 69 Alton 31 21
84 63 Bloomington 29 17
89 69 Cahokia 32 20
85 65 Champaign 30 18
88 66 Charleston 31 19
85 65 Danville 30 18
85 67 Decatur 29 19
85 65 Kankakee 29 18
83 64 Ottawa 28 18
86 66 Peoria 30 19
86 67 Quincy 30 19
87 66 Springfield 30 19

Southern Illinois

Average July temperature
High °F Low °F Place High °C Low °C
90 68 Belleville 32 20
89 70 Cairo 32 21
88 68 Carbondale 31 20
86 67 Mt Vernon 30 20
Reference

NOAA National Centers for Environmental Information (NCEI). Climate Normals.

Illinois Temperatures
Back to Top