Illinois May 1991 Average Temperature Rankings
1901-2000
Degrees Fahrenheit
1
68.6
62.1
6.5
125
5
1917
2018
1990
1977
top-tenth
2
62.3
56.8
5.5
127
3
1907
1896
1990
1977
top-tenth
3
56.2
51.1
5.1
127
3
1960
2012
1990
1977
top-tenth
4
50.7
45.7
5.0
128
2
1978
2012
1990
1991
top-tenth
2017
5
45.2
41.6
3.6
120
10
1978,1979
2012
1989
1990
top-tenth
1938,1946
6
42.7
39.6
3.1
118
11
1978
2012
1990
1987
top-tenth
2006
7
43.3
39.8
3.5
121
8
1904
2012
1990
1932
top-tenth
1998
8
44.5
41.6
2.9
119
10
1904,1978
2012
1990
1932
top-tenth
2006,2023
9
47.1
44.4
2.7
120
9
1904
2012
1990
1932
top-tenth
1998
10
49.6
47.3
2.3
119
10
1904
2012
1990
1932
top-tenth
2023
11
51.9
49.8
2.1
118
11
1904
2012
1990
1932
top-tenth
12
53.5
51.6
1.9
115
14
1904
2012
1990
1987
top-third
1942,1987,1992
18
49.3
47.6
1.7
110
18
1979
2017
1990
1988
top-third
1988,2022
24
52.7
51.6
1.1
104
24
1905
2017
1990
1988
top-third
1956,2001,2008
36
52.6
51.6
1.0
98
29
1979
2018
1990
1989
top-third
2005,2021
48
52.5
51.6
0.9
97
29
1980
2019
1990
1990
top-third
1923,1942,1988,1990,2004
60
52.7
51.6
1.1
107
18
1906,1907,1908,1981
2020
1990
1957
top-third
1936,1992,2001,2016