Illinois, Climate Division 9 August-May Average Temperature
Degrees Fahrenheit
1901-1940
-99
189605
52.1
0.6
189705
50.9
-0.6
189805
52.8
1.3
189905
49.2
-2.3
190005
51.5
0.0
190105
52.0
0.5
190205
49.8
-1.7
190305
52.0
0.5
190405
48.6
-2.9
190505
49.8
-1.7
190605
50.9
-0.6
190705
51.8
0.3
190805
51.5
0.0
190905
52.2
0.7
191005
51.4
-0.1
191105
51.9
0.4
191205
49.6
-1.9
191305
51.4
-0.1
191405
52.4
0.9
191505
51.1
-0.4
191605
51.4
-0.1
191705
50.8
-0.7
191805
48.5
-3.0
191905
52.5
1.0
192005
50.6
-0.9
192105
53.8
2.3
192205
53.0
1.5
192305
52.1
0.6
192405
50.4
-1.1
192505
52.5
1.0
192605
50.7
-0.8
192705
52.4
0.9
192805
51.4
-0.1
192905
51.3
-0.2
193005
51.3
-0.2
193105
51.6
0.1
193205
55.4
3.9
193305
51.7
0.2
193405
52.6
1.1
193505
52.7
1.2
193605
49.8
-1.7
193705
52.3
0.8
193805
52.7
1.2
193905
53.2
1.7
194005
49.9
-1.6