Illinois: Temperature Extremes

Month	Maximum °F	Year	Place	Minimum °F	Year	Place
Jan.	78	1986	Cahokia	–36	1999	Congerville
Feb.	83	2000	Kaskaskia River*	–35	1996	Elizabeth
March	94	1929	Harrisburg	–21	1962	Freeport
April	99	1989	Kaskaskia	–2	1982	Mount Carroll
May	107	1934	Sycamore*	21	1989	Elizabeth
June	108	1954	Palestine	29	1972	Marengo
July	117	1954	East St. Louis	35	1904	Lanark
Aug.	113	1934	La Harpe	31	1915	La Grange
Sept.	109	1925	Harrisburg	14	1899	Lanarck*
Oct.	98	1953	Harrisburg*	1	1925	La Harpe
Nov.	89	1987	Waterloo	–20	1947	Rockford
Dec.	79	1982	Cairo	–29	2000	Elizabeth*

*Also on earlier dates at the same time or other places.

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