Wilmington, DE: September

30 September 2026: September 2026 averaged 70.6°F in Wilmington, DE, the warmest September since 2025, 19th warmest of 113.

September 2026

Mean temperature: 70.6°F; Warmest since 2025; 19th warmest of 113
Precipitation: 5.73 in; Wettest since 2018; 25th wettest of 132

A normal September in Wilmington, DE (1991 to 2020): a mean temperature of 68.5°F, between 65.6°F and 71.9°F in eight years of ten and 4.55 in of precipitation, between 1.06 in and 7.31 in in eight years of ten.

The mean temperature of every September in Wilmington, DE since 1894: 70.6°F in 2026; the highest is 72.9°F, in 1895.

Normal range, 65.6 to 71.9°F

Every year, ranked, as a table

Every September in Wilmington, DE from 1894 to 2026, 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
2026	70.6	19	79.3	31	61.9	10	5.73	25	0
2025	71.1	15	81.2	16	61	16	1.86	106	0
2024	68.7	45	78	54	59.3	40	0.33	132	0
2023	69.4	33	78.5	45	60.3	26	5.08	34	0
2022	69.6	30	79.4	29	59.7	37	2.85	78	0
2021	70.3	22	80	23	60.7	18	5.36	29	0
2020	67.7	67	76.9	74	58.5	54	3.41	67	0
2019	72.3	4	83.2	4	61.3	14	0.48	129	0
2018	72.3	4	79.2	34	65.4	1	6.22	18	0
2017	70	26	79.7	25	60.4	24	1.12	119	0
2016	71.9	9	82.1	9	61.7	12	4.80	40	0
2015	72.4	3	82.9	5	62	9	2.50	86	0
2014	68.5	49	77.7	58	59.2	43	2.84	79	0
2013	66.1	90	77.4	65	54.8	100	1.92	104	0
2012	68.2	58	78	54	58.5	54	5.29	31	0
2011	69.8	27	77.3	68	62.2	7	5.93	23	0
2010	70.8	17	81.6	14	60	31	5.95	21	0
2009	66.6	86	74.9	99	58.3	58	4.91	36	0
2008	69.6	30	78.8	42	60.5	22	5.19	32	0
2007	70.5	20	81.9	12	59.1	45	0.49	127	0
2006	65.5	95	74	106	57	80	6.18	20	0
2005	71.8	10	83.3	3	60.3	26	0.44	131	0
2004	68.8	41	77.8	57	59.8	34	9.29	3	0
2003	68.5	49	76.9	74	60.1	29	7.39	6	0
2002	69.3	35	79.5	28	59.1	45	3.42	66	0
2001	65.6	94	75.7	91	55.5	94	2.57	85	0
2000	65	101	74.1	105	55.8	91	7.30	7	0
1999	68.1	62	76.3	86	59.9	32	12.68	1	0
1998	70.8	17	81.1	17	60.6	19	1.76	108	0
1997	65.5	95	75.6	93	55.3	98	1.93	103	0
1996	67.7	67	76.3	86	59	49	4.03	51	0
1995	68.3	55	78.2	49	58.3	58	5.17	33	0
1994	67.2	75	76.9	74	57.4	70	2.10	101	0
1993	68.7	45	78.2	49	59.2	43	6.26	17	0
1992	67.3	74	75.9	89	58.7	52	4.30	49	0
1991	67.2	75	77.2	71	57.1	79	5.36	29	0
1990	66.6	86	76.3	86	57	80	2.64	84	0
1989	68.4	53	77.7	58	59.1	45	4.31	48	0
1988	65.7	92	75.3	96	56.2	87	2.18	95	0
1987	68.3	55	76.9	74	59.7	37	4.85	39	0
1986	67.5	70	76.7	81	58.3	58	2.75	82	0
1985	69.1	38	79.3	31	58.9	51	4.56	45	0
1984	63.7	108	75	98	52.3	113	2.02	102	0
1983	69.2	37	81.3	15	57.2	76	3.44	65	0
1982	67.4	71	76.9	74	57.8	65	2.30	90	0
1981	66.9	81	76.4	84	57.4	70	3.82	55	0
1980	71.3	13	82.1	9	60.5	22	1.44	113	0
1979	68.2	58	77.3	68	59.1	45	5.94	22	0
1978	66.7	84	76.9	74	56.4	85	2.18	95	0
1977	69.3	35	77.5	62	61.1	15	1.29	115	0
1976	66.8	83	77.3	68	56.4	85	2.11	99	0
1975	65.4	97	74.2	104	56.5	84	6.19	19	0
1974	66.4	88	75.7	91	57.2	76	5.65	26	0
1973	70.4	21	80.3	21	60.4	24	3.02	75	0
1972	69.6	30	79.1	35	60.1	29	1.64	109	0
1971	71.1	15	78.3	47	63.9	2	6.99	11	0
1970	72.1	7	82.4	7	61.8	11	0.82	124	0
1969	68.1	62	77.6	61	58.7	52	6.84	12	0
1968	69.7	28	80.8	19	58.5	54	1.50	110	0
1967	65	101	75.5	95	54.6	103	1.16	117	0
1966	65.3	99	74.6	101	56	89	8.53	4	0
1965	69.4	33	78.9	40	59.9	32	2.41	88	0
1964	67.2	75	78.1	52	56.2	87	2.77	80	0
1963	63.7	108	73.5	109	53.9	107	3.50	62	0
1962	63.5	111	73.7	108	53.4	112	3.65	57	0
1961	72.5	2	82.2	8	62.8	4	2.33	89	0
1960	68	64	76.6	83	59.3	40	9.53	2	0
1959	70.3	22	80.1	22	60.6	19	2.29	91	0
1958	65.8	91	76.8	80	54.8	100	2.91	77	0
1957	68.6	47	77.5	62	59.8	34	6.55	16	0
1956	64.5	104	74	106	55.1	99	2.77	80	0
1955	67.2	75	77	72	57.4	70	2.27	92	0
1954	68.3	55	78.3	47	58.3	58	3.39	69	0
1953	68.2	58	79.7	25	56.7	83	3.64	58	0
1952	67.4	71	79.1	35	55.7	92	3.12	73	0
1951	66.9	81	78.2	49	55.7	92	1.16	117	0
1950	63.4	112	71.9	113	54.8	100	7.06	10	0
1949	64.2	105	74.6	101	53.9	107	3.08	74	0
1948	66.7	84	78.1	52	55.4	96	1.87	105	0
1947	67.4	71	77	72	57.9	64	2.19	94	0
1946	68.5	49	79.3	31	57.6	67	3.91	54	0
1945	70.1	25	80.5	20	59.8	34	4.41	46	0
1944	68.5	49	78.9	40	58	63	6.58	15	0
1943	67	79	79.7	25	54.3	105	0.45	130	0
1942	67.9	65	78.5	45	57.3	74	2.14	98	0
1941	70.2	24	83.6	1	56.9	82	0.73	126	0
1940	64.8	103	75.8	90	53.8	109			0
1939	68.6	47	79.4	29	57.6	67	0.87	122	1
1938	65.7	92	75.6	93	56	89	8.10	5	1
1937	65.4	97	76.4	84	54.2	106	2.69	83	1
1936	68.8	41	78	54	59.6	39	3.47	63	0
1935	65.2	100	74.8	100	55.5	94	6.60	14	0
1934	68.9	39	77.4	65	60.3	26	6.62	13	0
1933	69.7	28	78.8	42	60.6	19	3.46	64	0
1932	68.8	41	79.9	24	57.7	66	2.97	76	0
1931	72.1	7	81.9	12	62.3	6	1.24	116	0
1930	72.3	4	82.9	5	61.7	12	3.97	52	0
1929	68.2	58	79.1	35	57.4	70	4.69	43	0
1928	64.1	107	72.7	111	55.4	96	4.40	47	0
1927	67	79	76.7	81	57.2	76	3.13	72	0
1926	66.3	89	75.3	96	57.3	74	5.46	28	0
1925	71.4	12	82	11	60.8	17	1.83	107	0
1924	63.7	108	73	110	54.5	104	5.77	24	1
1923	68.9	39	78.8	42	59	49	4.79	41	0
1922	68.8	41	79.1	35	58.4	57	0.99	120	0
1921	71.8	10	81	18	62.6	5	3.56	61	0
1920	67.8	66	77.4	65	58.2	62	4.86	38	0
1919	67.6	69	77.7	58	57.5	69	3.22	71	0
1918	64.2	105	74.6	101	53.7	111	3.41	67	0
1917	63.4	112	72.7	111	53.8	109	3.59	59	1
1916							2.27	92	30
1915							0.49	127	30
1914							0.86	123	30
1913							3.33	70	30
1912							7.28	8	30
1911							2.18	95	30
1910							3.93	53	30
1909							3.73	56	30
1908							1.38	114	30
1907							5.55	27	30
1906							0.76	125	30
1905							4.95	35	30
1904							7.14	9	30
1903							2.50	86	30
1902							4.62	44	30
1901							3.57	60	30
1900							1.45	112	30
1899							4.12	50	30
1898							2.11	99	30
1897							1.48	111	30
1896	68.4	53	77.5	62	59.3	40	4.87	37	0
1895	72.9	1	83.5	2	62.2	7	0.93	121	0
1894	71.2	14	79	39	63.3	3	4.78	42	0

Warmest, coldest, wettest and driest

Warmest
Year	Mean, °F
1895	72.9
1961	72.5
2015	72.4
2019	72.3
2018	72.3
1930	72.3
1970	72.1
1931	72.1
2016	71.9
2005	71.8
More years share the last value

Coldest
Year	Mean, °F
1950	63.4
1917	63.4
1962	63.5
1984	63.7
1963	63.7
1924	63.7
1928	64.1
1949	64.2
1918	64.2
1956	64.5

Wettest
Year	Precipitation, in
1999	12.68
1960	9.53
2004	9.29
1966	8.53
1938	8.10
2003	7.39
2000	7.30
1912	7.28
1904	7.14
1950	7.06

Driest
Year	Precipitation, in
2024	0.33
2005	0.44
1943	0.45
2019	0.48
2007	0.49
1915	0.49
1941	0.73
1906	0.76
1970	0.82
1914	0.86

The hottest, coldest and wettest days

Hottest day: 93°F; 1 September 2026
Coldest night: 49°F; 24 September 2026
Wettest day: 1.58 in; 27 September 2026

Every month, season and year

Months

Seasons

Years

Wilmington, DE the day's answers

All-time records

Every answer in words

September 2026 brought 5.73 in of precipitation in Wilmington, DE, the wettest September since 2018, 25th wettest of 132.
The hottest day of September 2026 in Wilmington, DE: 93°F on Tuesday 1 September 2026.
The coldest night of September 2026 in Wilmington, DE: a low of 49°F on Thursday 24 September 2026.
The wettest day of September 2026 in Wilmington, DE: 1.58 in on Sunday 27 September 2026.