Knoxville AP Threshold Days by Year (USW00013891)

18 fixed thresholds counted per year at Knoxville AP (USW00013891): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Knoxville AP Thresholds

Knoxville AP: days with a maximum temperature at or above 30 C (86 F) in 117 years, most in 2010 with 115.
Knoxville AP: days with a maximum temperature at or above 90 F (32.2 C) in 117 years, most in 1936 with 78.
Knoxville AP: nights with a minimum temperature at or below 0 C (32 F) in 117 years, most in 1988 with 101.
Knoxville AP: nights with a minimum temperature at or above 20 C (68 F) in 117 years, most in 2018 with 91.
18 fixed thresholds have at least one qualifying day at Knoxville AP.

Days at or above 30 C (86 F)

117 years with a qualifying day

Days per year at Knoxville AP with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 115 in 2010.

Days at or above 30 C (86 F) per year at Knoxville AP
Year	Days	Decade average
1910	46	69.9
1911	98	69.9
1912	64	69.9
1913	85	69.9
1914	83	69.9
1915	61	69.9
1916	71	69.9
1917	49	69.9
1918	60	69.9
1919	82	69.9
1920	50	71.6
1921	87	71.6
1922	63	71.6
1923	61	71.6
1924	63	71.6
1925	107	71.6
1926	88	71.6
1927	75	71.6
1928	61	71.6
1929	61	71.6
1930	74	94.7
1931	102	94.7
1932	85	94.7
1933	106	94.7
1934	96	94.7
1935	90	94.7
1936	112	94.7
1937	91	94.7
1938	83	94.7
1939	108	94.7
1940	73	86.6
1941	110	86.6
1942	86	86.6
1943	98	86.6
1944	99	86.6
1945	89	86.6
1946	66	86.6
1947	82	86.6
1948	84	86.6
1949	79	86.6
1950	50	88.9
1951	87	88.9
1952	93	88.9
1953	98	88.9
1954	112	88.9
1955	96	88.9
1956	88	88.9
1957	94	88.9
1958	84	88.9
1959	87	88.9
1960	87	62.9
1961	45	62.9
1962	97	62.9
1963	46	62.9
1964	62	62.9
1965	81	62.9
1966	59	62.9
1967	26	62.9
1968	66	62.9
1969	60	62.9
1970	83	60.3
1971	49	60.3
1972	41	60.3
1973	44	60.3
1974	48	60.3
1975	75	60.3
1976	55	60.3
1977	86	60.3
1978	76	60.3
1979	46	60.3
1980	96	76.9
1981	73	76.9
1982	47	76.9
1983	78	76.9
1984	56	76.9
1985	63	76.9
1986	100	76.9
1987	102	76.9
1988	88	76.9
1989	66	76.9
1990	80	74
1991	82	74
1992	43	74
1993	93	74
1994	62	74
1995	86	74
1996	65	74
1997	56	74
1998	99	74
1999	74	74
2000	67	71.7
2001	64	71.7
2002	105	71.7
2003	44	71.7
2004	47	71.7
2005	82	71.7
2006	76	71.7
2007	109	71.7
2008	75	71.7
2009	48	71.7
2010	115	88.5
2011	99	88.5
2012	77	88.5
2013	56	88.5
2014	63	88.5
2015	76	88.5
2016	112	88.5
2017	72	88.5
2018	105	88.5
2019	110	88.5
2020	80	83
2021	72	83
2022	85	83
2023	71	83
2024	89	83
2025	79	83
2026	105	83

For each year, a bar from the first to the last day at Knoxville AP meeting 30 C (86 F).

First to last qualifying date each year at Knoxville AP
Year	First date	Last date
1910	1910-06-17	1910-10-03
1911	1911-05-10	1911-10-07
1912	1912-05-23	1912-09-17
1913	1913-05-03	1913-10-10
1914	1914-04-27	1914-09-22
1915	1915-04-25	1915-09-28
1916	1916-05-07	1916-10-07
1917	1917-04-18	1917-09-08
1918	1918-05-25	1918-10-06
1919	1919-04-09	1919-10-04
1920	1920-04-18	1920-09-27
1921	1921-04-24	1921-09-29
1922	1922-05-09	1922-10-04
1923	1923-06-03	1923-09-26
1924	1924-05-05	1924-09-01
1925	1925-04-23	1925-09-30
1926	1926-05-01	1926-10-04
1927	1927-04-18	1927-10-06
1928	1928-05-03	1928-09-16
1929	1929-03-24	1929-09-09
1930	1930-04-11	1930-09-24
1931	1931-05-17	1931-10-06
1932	1932-05-07	1932-09-19
1933	1933-05-11	1933-10-01
1934	1934-04-04	1934-09-28
1935	1935-04-26	1935-10-13
1936	1936-04-15	1936-09-28
1937	1937-04-18	1937-10-06
1938	1938-04-26	1938-10-18
1939	1939-05-06	1939-10-10
1940	1940-04-02	1940-09-24
1941	1941-04-19	1941-10-20
1942	1942-04-25	1942-09-19
1943	1943-04-26	1943-09-15
1944	1944-05-12	1944-10-04
1945	1945-03-25	1945-09-30
1946	1946-04-21	1946-09-27
1947	1947-05-15	1947-10-22
1948	1948-04-25	1948-09-22
1949	1949-05-05	1949-10-10
1950	1950-04-29	1950-09-20
1951	1951-04-30	1951-10-06
1952	1952-05-01	1952-10-01
1953	1953-05-22	1953-10-21
1954	1954-04-15	1954-10-13
1955	1955-04-17	1955-09-23
1956	1956-04-27	1956-09-17
1957	1957-04-24	1957-09-22
1958	1958-05-16	1958-09-26
1959	1959-05-02	1959-10-05
1960	1960-04-23	1960-09-22
1961	1961-06-02	1961-09-25
1962	1962-04-30	1962-09-15
1963	1963-03-31	1963-09-21
1964	1964-05-19	1964-09-11
1965	1965-04-23	1965-09-22
1966	1966-05-08	1966-09-04
1967	1967-05-26	1967-09-20
1968	1968-05-24	1968-09-08
1969	1969-05-07	1969-09-16
1970	1970-04-19	1970-09-26
1971	1971-06-03	1971-09-30
1972	1972-06-05	1972-09-20
1973	1973-06-03	1973-09-23
1974	1974-05-19	1974-09-12
1975	1975-05-21	1975-09-10
1976	1976-04-19	1976-09-09
1977	1977-05-15	1977-09-15
1978	1978-04-09	1978-09-21
1979	1979-05-11	1979-09-13
1980	1980-04-23	1980-09-24
1981	1981-06-05	1981-10-01
1982	1982-05-29	1982-10-05
1983	1983-06-14	1983-10-04
1984	1984-04-26	1984-09-25
1985	1985-05-14	1985-09-30
1986	1986-04-26	1986-10-04
1987	1987-04-21	1987-09-17
1988	1988-04-05	1988-09-23
1989	1989-04-26	1989-09-21
1990	1990-04-24	1990-09-12
1991	1991-05-15	1991-09-18
1992	1992-06-07	1992-09-21
1993	1993-05-07	1993-09-14
1994	1994-05-23	1994-09-16
1995	1995-04-10	1995-09-13
1996	1996-05-18	1996-09-07
1997	1997-05-18	1997-09-20
1998	1998-05-14	1998-10-07
1999	1999-06-02	1999-09-27
2000	2000-05-12	2000-09-20
2001	2001-04-10	2001-09-09
2002	2002-04-16	2002-10-03
2003	2003-06-11	2003-09-02
2004	2004-05-09	2004-09-06
2005	2005-05-12	2005-10-05
2006	2006-05-26	2006-09-18
2007	2007-05-01	2007-10-08
2008	2008-05-31	2008-09-14
2009	2009-04-24	2009-09-25
2010	2010-04-06	2010-09-24
2011	2011-04-10	2011-09-14
2012	2012-04-30	2012-09-07
2013	2013-05-21	2013-10-05
2014	2014-05-08	2014-09-19
2015	2015-05-07	2015-09-19
2016	2016-04-20	2016-10-20
2017	2017-04-29	2017-10-09
2018	2018-05-11	2018-10-08
2019	2019-04-29	2019-10-05
2020	2020-05-16	2020-09-13
2021	2021-05-21	2021-09-14
2022	2022-05-18	2022-09-21
2023	2023-04-05	2023-10-04
2024	2024-05-20	2024-09-24
2025	2025-04-03	2025-09-22
2026	2026-04-02	2026-10-14

Every Fixed Threshold

Fixed thresholds at Knoxville AP
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	117	115	2010	105
35 C (95 F): Days	83	34	1954	12
40 C (104 F): Days	2	2	2012	2
90 F (32.2 C): Days	117	78	1936	57
100 F (37.8 C): Days	21	8	1952	4
0 C (32 F): Ice days (max	111	18	2010	5
0 C (32 F): Frost days (min	117	101	1988	40
-10 C (14 F): Days with min	97	19	1985	5
-20 C (-4 F): Days with min	8	2	1966	1
-30 C (-22 F): Days with min	1	1	1985	1
20 C (68 F): Tropical nights (min	117	91	2018	96
25 C (77 F): Days with min	18	3	1952	1
10 mm (0.39 in): Days with 10 mm or more rain	117	60	2018	32
25 mm (0.98 in): Days with 25 mm or more rain	117	22	1991	14
50 mm (1.97 in): Days with 50 mm or more rain	101	7	2013	1
100 mm (3.94 in): Days with 100 mm or more rain	12	1	1917	1
10 cm (3.9 in): Days with 10 cm or more snowfall	49	5	1960	1
25 cm (9.8 in): Days with 25 cm or more snowfall	6	1	1942	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1910.

Download the Data

Data for Knoxville AP threshold days by year: CSV or JSON. Field meanings are on the data page.

Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-17 (17 October 2026). Threshold counts are computed by this site.

Data as of 2026-10-17. Last revised 17 October 2026 (2026-10-17).

Knoxville AP Threshold Days by Year (USW00013891)

Key Facts for Knoxville AP Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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