Illinois, Climate Division 9 36-Month Period Ending in May Average Temperature
Degrees Fahrenheit
1901-2000
-99
189805
55.9
0.5
189905
55.1
-0.3
190005
55.3
-0.1
190105
55.1
-0.3
190205
55.5
0.1
190305
55.6
0.2
190405
54.6
-0.8
190505
54.2
-1.2
190605
53.8
-1.6
190705
54.7
-0.7
190805
55.3
-0.1
190905
55.7
0.3
191005
55.6
0.2
191105
55.7
0.3
191205
55.0
-0.4
191305
55.0
-0.4
191405
55.3
-0.1
191505
56.0
0.6
191605
56.0
0.6
191705
55.4
0.0
191805
54.2
-1.2
191905
54.6
-0.8
192005
54.7
-0.7
192105
56.2
0.8
192205
56.6
1.2
192305
56.9
1.5
192405
56.1
0.7
192505
55.6
0.2
192605
55.3
-0.1
192705
55.8
0.4
192805
55.5
0.1
192905
55.4
0.0
193005
55.1
-0.3
193105
55.4
0.0
193205
56.8
1.4
193305
57.1
1.7
193405
57.4
2.0
193505
56.8
1.4
193605
56.1
0.7
193705
56.1
0.7
193805
55.8
0.4
193905
56.7
1.3
194005
55.9
0.5
194105
55.8
0.4
194205
55.9
0.5
194305
56.3
0.9
194405
56.2
0.8
194505
55.7
0.3
194605
55.8
0.4
194705
55.5
0.1
194805
55.4
0.0
194905
55.5
0.1
195005
55.9
0.5
195105
55.2
-0.2
195205
54.8
-0.6
195305
55.0
-0.4
195405
56.4
1.0
195505
57.1
1.7
195605
56.7
1.3
195705
56.4
1.0
195805
55.2
-0.2
195905
55.1
-0.3
196005
54.3
-1.1
196105
54.5
-0.9
196205
54.5
-0.9
196305
54.5
-0.9
196405
54.9
-0.5
196505
55.0
-0.4
196605
55.3
-0.1
196705
55.2
-0.2
196805
54.5
-0.9
196905
54.4
-1.0
197005
53.8
-1.6
197105
54.4
-1.0
197205
55.1
-0.3
197305
55.3
-0.1
197405
56.1
0.7
197505
55.4
0.0
197605
55.9
0.5
197705
54.4
-1.0
197805
53.9
-1.5
197905
53.0
-2.4
198005
53.5
-1.9
198105
54.5
-0.9
198205
54.8
-0.6
198305
55.1
-0.3
198405
54.5
-0.9
198505
55.0
-0.4
198605
55.2
-0.2
198705
56.0
0.6
198805
55.9
0.5
198905
55.8
0.4
199005
55.4
0.0
199105
55.9
0.5
199205
56.4
1.0
199305
55.9
0.5
199405
55.1
-0.3
199505
54.9
-0.5
199605
55.1
-0.3
199705
55.1
-0.3
199805
55.1
-0.3
199905
56.1
0.7
200005
57.2
1.8
200105
56.7
1.3
200205
56.5
1.1
200305
55.9
0.5
200405
56.5
1.1
200505
56.2
0.8
200605
56.8
1.4
200705
56.8
1.4
200805
56.8
1.4
200905
56.2
0.8
201005
55.8
0.4
201105
55.9
0.5
201205
57.2
1.8
201305
57.4
2.0
201405
56.5
1.1