Waterloo, IA: December

31 December 2025: December 2025 averaged 20.9°F in Waterloo, IA, the coldest December since 2013, 48th coldest of 131.

December 2025

Mean temperature: 20.9°F; Coldest since 2013; 48th coldest of 131
Precipitation: 0.58 in; Driest since 2017; 29th driest of 131

A normal December in Waterloo, IA (1991 to 2020): a mean temperature of 26°F, between 16.7°F and 30°F in eight years of ten and 1.24 in of precipitation, between 0.41 in and 2.40 in in eight years of ten.

The mean temperature of every December in Waterloo, IA since 1895: 20.9°F in 2025; the lowest is 6.6°F, in 1983.

Normal range, 16.7 to 30°F

Every year, ranked, as a table

Every December in Waterloo, IA from 1895 to 2025, ranked: the mean temperature, the mean high and the mean low from the warmest, the precipitation from the wettest; a year missing more than a tenth of its days is not ranked.

Year	Mean, °F	Rank	High, °F	Rank	Low, °F	Rank	Precipitation, in	Rank	Days missing
2025	20.9	84	30.5	78	11.2	90	0.58	102	0
2024	28.8	19	36.2	31	21.3	15	1.45	46	0
2023	34.8	1	43.5	1	26.2	3	0.85	78	0
2022	22	76	30.5	78	13.4	73	1.59	37	0
2021	31.4	9	40.9	5	21.8	10	1.32	51	0
2020	26.7	36	36.6	27	16.9	51	1.01	70	0
2019	30	14	39.5	12	20.5	20	0.92	75	0
2018	29.1	17	37.1	24	21.2	16	2.60	6	0
2017	21.9	78	31.3	69	12.5	82	0.46	112	0
2016	22.1	75	28.3	89	15.9	59	1.87	25	0
2015	33.9	2	39.9	7	27.8	1	5.92	1	0
2014	28	25	34.3	44	21.7	11	1.64	34	0
2013	14.7	123	24.3	118	5.2	120	0.94	74	0
2012	26.5	40	35.8	34	17.1	50	1.74	32	0
2011	29.6	16	38	19	21.2	16	2.38	8	0
2010	16.9	112	25.1	116	8.7	106	2.05	14	0
2009	18.8	100	26.5	108	11	94	3.19	3	0
2008	14.9	122	26.1	110	3.6	125	2.01	16	0
2007	18.9	98	26.4	109	11.4	86	1.92	23	0
2006	30.7	11	39.9	7	21.4	14	1.86	26	0
2005	17.1	111	24.2	119	10	101	1.12	62	0
2004	25.4	50	34.8	40	16	58	0.52	105	0
2003	27.2	32	35.4	37	19	31	0.47	110	0
2002	28.9	18	40.2	6	17.7	42	0.14	131	0
2001	30.3	13	39.5	12	21.1	19	0.70	95	0
2000	8.5	130	16.5	130	0.6	128	1.91	24	0
1999	25.9	47	36.4	28	15.4	64	0.43	116	0
1998	28.5	21	38.8	15	18.2	35	0.25	127	0
1997	26.7	36	32.1	65	21.2	16	0.78	87	0
1996	18.5	103	25.9	112	11.1	92	1.05	68	0
1995	23.5	68	31.2	71	15.9	59	0.16	130	0
1994	26.2	42	34.4	43	18.1	37	1.35	49	0
1993	25.3	54	33.3	57	17.3	48	0.76	90	0
1992	23.5	68	31.3	69	15.6	61	1.60	36	0
1991	26.2	42	33.9	47	18.5	34	1.54	39	0
1990	18.1	105	27.6	95	8.7	106	1.26	54	0
1989	13.1	124	22.1	125	4.1	123	0.22	129	0
1988	23.4	70	33.4	56	13.4	73	0.52	105	0
1987	27	33	33.8	48	20.2	23	1.82	28	0
1986	24.3	62	30.9	74	17.6	44	0.82	81	0
1985	8.8	129	20.1	128	-2.4	131	1.25	55	0
1984	24	64	33.6	52	14.3	69	1.95	18	0
1983	6.6	131	14.4	131	-1.2	130	1.03	69	0
1982	29.9	15	38.1	18	21.7	11	3.77	2	0
1981	19.6	89	27.9	92	11.3	87	0.83	79	0
1980	22.2	74	30.3	80	14.1	70	0.52	105	0
1979	28.3	23	38.5	17	18.1	37	0.71	93	0
1978	19.5	90	27.4	99	11.6	85	0.79	86	0
1977	16.7	114	24	120	9.5	103	1.73	33	0
1976	12.7	125	24.8	117	0.6	128	0.46	112	0
1975	25.3	54	33.1	61	17.5	47	0.40	120	0
1974	24.4	61	30.8	75	18	40	1.28	53	0
1973	20.3	85	27.6	95	12.9	78	2.26	10	0
1972	16.1	116	23.7	122	8.5	109	1.84	27	0
1971	23.9	65	31.1	72	16.7	52	1.78	30	0
1970	19.4	92	28.8	86	9.9	102	1.13	61	0
1969	17.3	108	25.9	112	8.7	106	1.95	18	0
1968	18.6	102	26.8	104	10.4	100	2.80	4	0
1967	25	57	33.7	51	16.4	55	0.83	79	0
1966	22.5	71	31.4	68	13.7	71	0.80	83	0
1965	32.6	5	41.7	3	23.5	6	2.12	12	0
1964	19.1	94	27.2	101	11	94	1.93	21	0
1963	10.3	128	19.5	129	1.2	127	0.52	105	0
1962	21.5	80	30.8	75	12.2	84	0.28	124	0
1961	18.5	103	27.6	95	9.4	105	1.29	52	0
1960	20.3	85	30	82	10.5	99	0.71	93	0
1959	32.4	6	39.7	10	25	4	1.78	30	0
1958	19	96	28.7	87	8.5	109	0.40	120	1
1957	27.8	27	35.9	33	19.6	26	0.68	96	0
1956	24.6	58	33.6	52	15.6	61	0.41	118	0
1955	17.3	108	26.6	106	8	113	0.46	112	0
1954	26	46	32.9	62	19.1	30	0.96	73	0
1953	27.5	28	35.6	35	19.3	28	1.06	66	0
1952	26.1	45	32.4	64	19.8	24	1.18	58	0
1951	20.1	87	29	84	11.2	90	1.35	49	0
1950	16.1	116	26.1	110	6.1	119	0.23	128	0
1949	25.7	48	35.3	39	16.2	56	0.59	100	0
1948	24.5	60	33.5	54	15.6	61	1.55	38	0
1947	26.6	38	33.8	48	19.5	27	1.52	40	0
1946	28.1	24	38.7	16	17.6	44	0.80	83	0
1945	17.4	107	25.3	114	9.5	103	1.64	34	0
1944	19.1	94	27.5	98	10.7	97	1.36	48	0
1943	25.4	50	36.4	28	14.5	68	0.82	81	0
1942	18.9	98	26.8	104	11	94	1.06	66	0
1941	31.5	7	39.8	9	23.3	8	1.93	21	0
1940	27.3	30	34	46	20.5	20	1.48	44	0
1939	31.4	9	41.3	4	21.5	13	0.27	126	0
1938	25.7	48	33.2	58	18.2	35	1.11	63	0
1937	21	83	28.6	88	13.5	72	0.68	96	0
1936	27.9	26	37.2	23	18.7	33	1.07	65	0
1935	19.9	88	27.1	102	12.7	80	1.14	60	0
1934	19.2	93	27.4	99	11.1	92	0.58	102	0
1933	24.3	62	33.8	48	14.9	66	1.21	56	0
1932	21.3	81	30.1	81	12.5	82	2.38	8	0
1931	33.5	3	39.5	12	27.5	2	2.19	11	0
1930	24.6	58	33.2	58	16.1	57	0.67	98	0
1929	23.7	67	32.5	63	15	65	0.43	116	0
1928	26.6	38	35.4	37	17.7	42	1.15	59	0
1927	17.3	108	28.1	90	6.5	117	1.39	47	0
1926	21.1	82	29.3	83	12.9	78	0.87	76	0
1925	18	106	28.1	90	8	113	2.03	15	0
1924	15.2	120	24	120	6.3	118	1.50	43	0
1923	33.3	4	42.6	2	23.9	5	0.78	87	0
1922	23.9	65	34.5	42	13.3	75	0.28	124	0
1921	27	33	36.3	30	17.6	44	1.09	64	0
1920	25.4	50	33.5	54	17.3	48	1.21	56	0
1919	12.2	126	20.7	127	3.8	124	0.41	118	0
1918	30.6	12	37.8	21	23.4	7	0.78	87	0
1917	12	127	21	126	2.9	126	0.50	109	0
1916	16.5	115	27.8	93	5.2	120	0.86	77	0
1915	22	76	31	73	13	76	0.67	98	0
1914	15	121	25.2	115	4.9	122	1.48	44	0
1913	31.5	7	39.7	10	23.3	8	1.01	70	0
1912	27.4	29	38	19	16.7	52	0.80	83	0
1911	27.3	30	35.6	35	19	31	1.97	17	0
1910	22.5	71	32.1	65	13	76	0.47	110	0
1909	15.7	118	22.8	124	8.5	109	2.55	7	0
1908	25.4	50	36.1	32	14.7	67	0.57	104	0
1907	28.6	20	36.7	26	20.5	20	0.72	92	0
1906	26.2	42	33.2	58	19.3	28	2.10	13	0
1905	26.8	35	37.1	24	16.5	54	0.73	91	0
1904	22.4	73	34.1	45	10.7	97	2.66	5	0
1903	18.7	101	28.9	85	8.5	109	0.37	122	0
1902	19.5	90	27.8	93	11.3	87	1.94	20	0
1901	19	96	26.6	106	11.3	87	0.59	100	0
1900	26.3	41	34.7	41	17.9	41	0.98	72	0
1899	21.7	79	30.7	77	12.7	80	1.80	29	0
1898	16.9	112	26.9	103	6.8	116	0.33	123	0
1897	15.3	119	23.7	122	6.9	115	1.52	40	0
1896	28.5	21	37.3	22	19.7	25	0.45	115	0
1895	25.1	56	32.1	65	18.1	37	1.52	40	0

Warmest, coldest, wettest and driest

Warmest
Year	Mean, °F
2023	34.8
2015	33.9
1931	33.5
1923	33.3
1965	32.6
1959	32.4
1941	31.5
1913	31.5
2021	31.4
1939	31.4

Coldest
Year	Mean, °F
1983	6.6
2000	8.5
1985	8.8
1963	10.3
1917	12
1919	12.2
1976	12.7
1989	13.1
2013	14.7
2008	14.9

Wettest
Year	Precipitation, in
2015	5.92
1982	3.77
2009	3.19
1968	2.80
1904	2.66
2018	2.60
1909	2.55
2011	2.38
1932	2.38
1973	2.26

Driest
Year	Precipitation, in
2002	0.14
1995	0.16
1989	0.22
1950	0.23
1998	0.25
1939	0.27
1962	0.28
1922	0.28
1898	0.33
1903	0.37

The hottest, coldest and wettest days

Hottest day: 44°F; 9 December 2025
Coldest night: -15°F; 4 December 2025
Wettest day: 0.22 in; 6 December 2025

Every month, season and year

Months

Seasons

Years

Waterloo, IA the day's answers

All-time records

Every answer in words

December 2025 brought 0.58 in of precipitation in Waterloo, IA, the driest December since 2017, tied 29th driest of 131 (with 1934).
The hottest day of December 2025 in Waterloo, IA: 44°F on Tuesday 9 December 2025.
The coldest night of December 2025 in Waterloo, IA: a low of -15°F on Thursday 4 December 2025.
The wettest day of December 2025 in Waterloo, IA: 0.22 in on Saturday 6 December 2025.