Ontario, OR: September

30 September 2026: September 2026 averaged 62.6°F in Ontario, OR, the coldest September since 2005, 22nd coldest of 70.

September 2026

Mean temperature: 62.6°F; Coldest since 2005; 22nd coldest of 70
Precipitation: 0.41 in; Wettest since 2025; 26th wettest of 79

A normal September in Ontario, OR (1991 to 2020): 0.13 in of precipitation, between 0.01 in and 0.79 in in eight years of ten.

The mean temperature of every September in Ontario, OR since 1945: 62.6°F in 2026; the lowest is 58.9°F, in 1945.

Every year, ranked, as a table

Every September in Ontario, OR from 1945 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	62.6	49	78.4	60	46.8	29	0.41	26	0
2025	67.8	6	84.1	18	51.5	5	0.41	26	0
2024	68.7	4	85.7	12	51.6	4	0.12	51	0
2023	66.8	11	82	31	51.5	5	0.28	38	1
2022	69.6	1	87.1	5	52	3	trace	72	0
2021	64.9	25	82.7	26	47	26	0.28	38	0
2020	65.1	23	83.3	20	46.6	30	0.08	57	1
2019	65.7	17	80.4	43	51.1	7	1.07	7	0
2018	64.5	28	81.6	33	47.4	20	0.02	68	0
2017	64.9	25	80	48	49.8	11	0.40	29	0
2016	63.4	40	79.5	51	47.3	21	0.05	63	0
2015	64.1	32	81	38	47.1	22	0.45	23	0
2014	66.6	13	82	31	51.1	7	0.42	25	0
2013	66.1	14	79.1	55	53	2	1.16	6	0
2012	65.8	15	83.6	19	48	18	0.08	57	0
2011	67.5	8	85.9	11	49.1	14	0.14	48	0
2010	64.1	32	81.2	37	47.1	22	0.03	67	0
2009	67.3	9	85.1	15	49.6	12	trace	72	0
2008	63.1	45	80.1	47	46	39	1.01	9	0
2007	63.2	44	79.4	53	47.1	22	0.69	15	0
2006	62.7	48	80.3	44	45.1	45	0.36	33	1
2005	61.9	53	79	56	44.9	47	0.11	54	1
2004	62	52	76.9	73	47.1	22	0.11	54	0
2003	63.5	39	80.7	40	46.3	35	0.14	48	0
2002	64.2	30	81.4	35	47	26	0.26	42	0
2001	65.5	18	82.8	24	48.2	17	0.07	59	1
2000	61.7	55	77.5	68	45.8	41	0.32	35	0
1999	62.4	51	79.3	54	45.4	42	0.00	76	0
1998	68	5	82.8	24	53.2	1	0.55	20	0
1997	65.3	22	81	38	49.6	12			1
1996			77.5	68					5
1995			83.1	21			0.05	63	4
1994	65.4	21	85.1	15	44.8	48	0.09	56	3
1993			82.9	23	42.9	66	0.00	76	4
1992			80.7	40	43.1	63	0.02	68	4
1991					45.9	40	0.28	38	7
1990					50.2	10	0.02	68	4
1989					44	56	1.28	5	7
1988					41.5	74	0.06	60	7
1987					43.1	63	0.00	76	6
1986					43.8	58	1.36	4	6
1985					42	71	1.61	3	7
1984	61.3	58	79.6	50	42.9	66	0.06	60	0
1983	61.1	59	78.1	64	44.3	55	0.13	50	1
1982	60.7	63	78	66	43.4	61	0.72	13	0
1981	63.9	36	82.7	26	45	46	0.52	21	0
1980	63.4	40	80.3	44	46.6	30	1.91	2	0
1979	66.9	10	86.8	7	46.9	28	0.12	51	0
1978	60.8	62	78.1	64	43.3	62	0.69	15	1
1977	62.9	47	79.5	51	46.3	35	0.73	12	0
1976	64	35	81.6	33	46.4	33	1.00	10	0
1975	64.5	28	85.6	13	43.5	60	trace	72	0
1974	64.2	30	86.2	10	42.2	69	0.00	76	0
1973	63.6	38	82.4	28	44.8	48	0.89	11	0
1972	59.9	65	79	56	40.7	75	0.29	37	0
1971	59.4	68	78.9	58	39.9	79	0.21	43	0
1970	59	69	78	66	40	78	1.07	7	0
1969	65.8	15	85.2	14	46.3	35	0.37	32	0
1968	63.1	45	81.4	35	44.7	50	0.05	63	0
1967	69.2	3	89.9	1	48.5	15	0.63	17	0
1966	69.5	2	88.3	2	50.7	9	0.33	34	0
1965	59.7	66	77.3	70	42	71	0.17	45	0
1964	61	61	80.3	44	41.7	73	0.27	41	0
1963	67.6	7	86.8	7	48.4	16	0.39	30	0
1962	65	24	86.3	9	43.6	59	0.41	26	0
1961	60.3	64	78.2	62	42.5	68	0.71	14	0
1960	66.7	12	88.1	3	45.3	43	0.60	18	0
1959	61.5	56	76.8	74	46.2	38	2.76	1	0
1958	63.4	40	82.4	28	44.5	53	0.47	22	0
1957	65.5	18	87.9	4	43	65	0.02	68	0
1956	63.8	37	87.1	5	40.5	77	0.04	66	0
1954	61.1	59	78.3	61	44	56	0.39	30	0
1953	65.5	18	84.5	17	46.4	33	trace	72	0
1952	64.1	32	83	22	45.3	43	0.58	19	0
1951	62.5	50	80.5	42	44.5	53	0.15	47	0
1950	63.3	43	80	48	46.5	32	0.06	60	0
1949	64.9	25	82.3	30	47.5	19	0.19	44	0
1948	61.5	56	78.2	62	44.7	50	0.12	51	0
1947	61.8	54	78.9	58	44.6	52	0.31	36	0
1946	59.6	67	77	72	42.2	69	0.17	45	0
1945	58.9	70	77.3	70	40.6	76	0.44	24	0

Warmest, coldest, wettest and driest

Warmest
Year	Mean, °F
2022	69.6
1966	69.5
1967	69.2
2024	68.7
1998	68
2025	67.8
1963	67.6
2011	67.5
2009	67.3
1979	66.9

Coldest
Year	Mean, °F
1945	58.9
1970	59
1971	59.4
1946	59.6
1965	59.7
1972	59.9
1961	60.3
1982	60.7
1978	60.8
1964	61

Wettest
Year	Precipitation, in
1959	2.76
1980	1.91
1985	1.61
1986	1.36
1989	1.28
2013	1.16
2019	1.07
1970	1.07
2008	1.01
1976	1.00

Driest
Year	Precipitation, in
1999	0.00
1993	0.00
1987	0.00
1974	0.00
2022	trace
2009	trace
1975	trace
1953	trace
2018	0.02
1992	0.02
More years share the last value

The hottest, coldest and wettest days

Hottest day: 89°F; 24 September 2026
Coldest night: 37°F; 15 September 2026
Wettest day: 0.36 in; 3 September 2026

Every month, season and year

Months

Seasons

Years

Ontario, OR the day's answers

All-time records

Every answer in words

September 2026 brought 0.41 in of precipitation in Ontario, OR, the wettest September since 2025, tied 26th wettest of 79 (with 2025 and 1962).
The hottest day of September 2026 in Ontario, OR: 89°F on Thursday 24 September 2026.
The coldest night of September 2026 in Ontario, OR: a low of 37°F on Tuesday 15 September 2026.
The wettest day of September 2026 in Ontario, OR: 0.36 in on Thursday 3 September 2026.