Average Temperature in Illinois by Year

This page is a list of the average statewide temperature in the U.S. state of Illinois for each year from 1895–2023. It is a statewide average over the entire territory of the state, based on data from the NOAA.

State:

Month:

What Was the Hottest Year in Illinois History?

2012 was the warmest year in Illinois history. Statewide, the average daily high temperature was 66.8 °F, and the average low was 44.7 °F.

What Was the Coldest Year in Illinois History?

1917 was the coolest year in Illinois history. Statewide, the average daily high temperature was 59.2 °F, and the average low was 37.4 °F.

Click column headers to sort

Year	Rank	High (°F)	Low (°F)
2023	5	65.3	44.2
2022	48	62.5	41.6
2021	11	63.6	44.0
2020	23	63.2	43.4
2019	48	61.8	42.4
2018	40	62.3	42.6
2017	7	64.8	44.0
2016	6	64.5	45.0
2015	30	62.9	42.9
2014	124	59.5	39.5
2013	84	61.1	41.1
2012	1	66.8	44.7
2011	27	62.9	43.4
2010	30	63.1	42.7
2009	74	61.1	41.8
2008	90	61.1	40.8
2007	12	64.1	43.2
2006	10	64.1	43.9
2005	12	64.0	43.4
2004	37	62.6	42.6
2003	67	62.1	41.3
2002	24	63.4	43.1
2001	21	63.7	43.1
2000	45	62.4	42.0
1999	20	64.3	42.8
1998	2	64.6	45.8
1997	88	60.7	41.2
1996	117	60.2	40.0
1995	71	61.8	41.4
1994	53	62.4	41.6
1993	90	60.0	41.7
1992	60	61.7	42.0
1991	12	63.8	43.7
1990	18	63.8	43.3
1989	109	60.9	40.0
1988	48	63.7	40.5
1987	8	64.6	43.6
1986	32	62.8	42.8
1985	102	60.8	40.5
1984	63	61.7	41.9
1983	53	61.7	42.2
1982	99	60.7	40.6
1981	63	62.0	41.6
1980	78	61.6	41.1
1979	125	59.7	39.1
1978	123	59.7	39.4
1977	73	61.8	41.2
1976	109	61.8	39.0
1975	53	61.8	42.2
1974	71	61.4	41.8
1973	28	62.4	43.7
1972	113	60.2	40.5
1971	45	62.8	41.6
1970	83	61.2	41.2
1969	109	60.3	40.4
1968	84	61.4	40.8
1967	102	60.7	40.3
1966	102	61.2	40.0
1965	53	62.3	41.6
1964	40	63.5	41.5
1963	99	62.0	39.4
1962	90	61.3	40.5
1961	84	61.4	40.8
1960	113	60.4	40.3
1959	60	62.1	41.6
1958	118	60.2	39.9
1957	63	61.8	41.9
1956	35	63.7	41.6
1955	42	63.3	41.5
1954	12	64.5	42.9
1953	12	65.1	42.3
1952	37	63.6	41.6
1951	119	60.0	39.8
1950	121	60.1	39.5
1949	32	63.3	42.2
1948	67	62.3	41.0
1947	78	61.3	41.2
1946	12	64.7	42.7
1945	99	60.7	40.6
1944	43	62.6	41.9
1943	88	61.7	40.2
1942	67	61.8	41.6
1941	21	63.6	43.2
1940	107	61.0	40.0
1939	24	64.3	42.2
1938	8	64.6	43.6
1937	102	60.7	40.4
1936	60	63.1	40.6
1935	78	60.9	41.6
1934	24	64.3	42.2
1933	18	64.5	42.7
1932	53	62.8	41.3
1931	4	65.1	44.7
1930	37	63.6	41.5
1929	119	60.3	39.4
1928	74	61.7	41.1
1927	53	62.3	41.7
1926	109	60.4	40.3
1925	63	62.8	40.7
1924	127	59.8	38.7
1923	67	62.0	41.4
1922	28	64.0	42.0
1921	3	65.4	44.6
1920	95	61.2	40.4
1919	48	62.8	41.4
1918	78	62.2	40.4
1917	129	59.2	37.4
1916	84	62.2	40.0
1915	90	60.9	40.9
1914	53	62.8	41.1
1913	32	63.6	42.0
1912	125	59.8	38.9
1911	35	63.3	42.2
1910	95	61.9	39.8
1909	90	61.5	40.3
1908	43	63.3	41.3
1907	107	60.7	40.2
1906	74	62.0	40.8
1905	113	61.1	39.4
1904	128	59.6	38.0
1903	116	60.8	39.5
1902	102	60.9	40.4
1901	95	62.2	39.4
1900	48	62.7	41.5
1899	95	61.4	40.3
1898	78	61.1	41.5
1897	74	62.0	40.8
1896	45	62.5	41.9
1895	122	60.9	38.5