Average Annual Temperatures in Illinois
Average annual temperatures for cities throughout Illinois are listed below.
The tables give the normal maximum and minimum yearly temperatures based on weather data collected from 1981 to 2010 by the US National Climatic Data Center.
You can jump to a separate table for each region of the state: Chicago Area, Northern Illinois, Central Illinois and Southern Illinois.
Chicago Area
| High °F | Low °F | Place | High °C | Low °C |
|---|---|---|---|---|
| 59 | 41 | Aurora | 15 | 5 |
| 58 | 40 | Chicago Botanical Garden | 15 | 5 |
| 59 | 44 | Chicago Midway Airport | 15 | 6 |
| 59 | 41 | Chicago O'Hare Airport | 15 | 5 |
| 61 | 45 | Chicago University | 16 | 7 |
| 59 | 39 | Elgin | 15 | 4 |
| 60 | 41 | Joliet | 16 | 5 |
Northern Illinois
| High °F | Low °F | Place | High °C | Low °C |
|---|---|---|---|---|
| 57 | 39 | Antioch | 14 | 4 |
| 58 | 39 | DeKalb | 14 | 4 |
| 58 | 38 | Dixon | 15 | 4 |
| 58 | 38 | Freeport | 15 | 3 |
| 61 | 41 | Moline | 16 | 5 |
| 59 | 39 | Rockford | 15 | 4 |
| 57 | 39 | Waukegan | 14 | 4 |
Central Illinois
| High °F | Low °F | Place | High °C | Low °C |
|---|---|---|---|---|
| 66 | 48 | Alton | 19 | 9 |
| 66 | 46 | Cahokia | 19 | 8 |
| 63 | 43 | Danville | 17 | 6 |
| 62 | 42 | Peoria | 16 | 6 |
| 62 | 43 | Quincy | 17 | 6 |
| 63 | 43 | Springfield | 17 | 6 |
| 62 | 42 | Urbana | 17 | 5 |
Southern Illinois
| High °F | Low °F | Place | High °C | Low °C |
|---|---|---|---|---|
| 68 | 47 | Cairo | 20 | 9 |
| 64 | 44 | Marion | 18 | 6 |
| 64 | 44 | Mt Vernon | 18 | 7 |
Reference
National Climatic Data Center. NOAA's 1981-2010 Climate Normals.