Illinois December Weather

Illinois weather averages and all-time records in the month of December from 1991–2020 based on data made available by the NOAA.

State:

Month:

Statewide December Averages
High temperature	39.4 °F
Low temperature	23.7 °F
Precipitation	2.4 inches

Illinois Cities

December weather averages for various places in Illinois, from 1991–2020.

City	Average (°F)		Record (°F)		Monthly (inches)
City	High	Low	High	Low	Precipitation	Snow
Aledo	35.7	19.7	73	-22	2.0	4.7
Aurora	36.1	20.8	70	-25	2.2	6.7
Belleville	46.0	28.4	77	-19	2.6	2.5
Bloomington-Normal	38.0	21.6	72	-22	2.3	4.4
Carbondale	45.5	27.2	77	-14	3.7	2.7
Carlyle	42.3	26.3	74	-14	3.2	n/a
Champaign	38.6	23.4	73	-20	2.1	n/a
Charleston	41.5	25.9	73	-20	2.8	4.3
Chicago	37.4	24.8	72	-20	2.3	7.8
Danville	39.9	24.9	72	-25	2.6	3.0
Decatur	40.2	24.8	72	-22	2.3	2.9
Dixon	35.0	19.5	68	-25	2.1	8.0
Du Quoin	45.0	28.4	76	-15	3.2	2.9
Elgin	35.3	20.1	68	-24	2.2	7.5
Elizabeth	33.6	16.2	71	-29	2.0	8.0
Fairfield	43.9	27.5	74	-18	3.3	4.1
Freeport	33.6	17.9	69	-29	1.8	8.5
Galesburg	35.6	21.1	72	-22	2.1	5.8
Geneseo	35.7	20.9	70	-20	2.1	7.2
Hoopeston	37.9	23.9	72	-22	2.1	5.2
Jacksonville	41.2	23.0	74	-21	1.9	4.3
Joliet	36.7	22.1	70	-20	2.0	3.8
Kankakee	38.0	21.7	71	-26	2.2	4.8
Kewanee	35.0	19.2	70	-24	2.1	7.2
Lincoln	39.2	22.8	72	-29	2.4	4.8
Moline	36.5	20.7	75	-24	2.0	8.8
Monmouth	37.6	21.3	73	-22	2.1	5.8
Morris	37.1	21.7	72	-26	2.1	5.1
Morrison	36.3	18.3	73	-28	2.0	6.9
Mt. Vernon	43.0	25.9	78	-19	2.8	2.5
Olney	42.8	26.4	74	-19	3.5	3.5
Ottawa	37.3	21.1	71	-23	1.9	5.6
Pana	41.6	25.0	74	-20	2.5	3.0
Paris	39.5	24.5	73	-22	2.7	4.3
Peoria	38.0	23.1	71	-24	2.2	6.0
Quincy	39.3	23.9	75	-22	1.8	n/a
Rantoul	39.3	21.8	75	-22	2.1	2.0
Rockford	34.4	19.7	69	-24	1.9	9.0
Springfield	40.3	24.8	74	-21	2.1	4.1
Tuscola	39.8	24.9	71	-26	2.5	3.6