Iron Knob Threshold Days by Year

3 fixed thresholds counted per year at Iron Knob (ASN00018034): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Iron Knob Thresholds

Iron Knob: days with 10 mm (0.39 in) or more of precipitation in 97 years, most in 1917 with 13.
Iron Knob: days with 25 mm (0.98 in) or more of precipitation in 53 years, most in 1973 with 5.
Iron Knob: days with 50 mm (1.97 in) or more of precipitation in 19 years, most in 1921 with 3.
3 fixed thresholds have at least one qualifying day at Iron Knob.

Days with 10 mm (0.39 in) or more of precipitation

97 years with a qualifying day

Days per year at Iron Knob with 10 mm (0.39 in) or more of precipitation, with the decade average as a line. The most was 13 in 1917.

Days with 10 mm (0.39 in) or more of precipitation per year at Iron Knob
Year	Days	Decade average
1911	7	5.6
1912	6	5.6
1913	4	5.6
1914	2	5.6
1915	3	5.6
1916	7	5.6
1917	13	5.6
1918	2	5.6
1919	6	5.6
1921	8	4.1
1922	2	4.1
1923	5	4.1
1924	4	4.1
1925	4	4.1
1927	2	4.1
1928	4	4.1
1929	4	4.1
1930	5	4.1
1931	5	4.1
1932	9	4.1
1933	3	4.1
1934	2	4.1
1935	4	4.1
1936	4	4.1
1937	5	4.1
1938	2	4.1
1939	2	4.1
1940	2	3.4
1942	6	3.4
1944	2	3.4
1945	4	3.4
1946	2	3.4
1947	5	3.4
1948	2	3.4
1949	4	3.4
1950	3	3.9
1951	4	3.9
1952	6	3.9
1953	3	3.9
1954	7	3.9
1955	4	3.9
1956	2	3.9
1958	4	3.9
1959	2	3.9
1960	4	4.3
1961	4	4.3
1962	3	4.3
1964	3	4.3
1965	2	4.3
1966	8	4.3
1967	4	4.3
1968	6	4.3
1969	5	4.3
1971	7	9.4
1972	6	9.4
1973	12	9.4
1974	13	9.4
1979	9	9.4
1980	4	5.2
1981	8	5.2
1982	2	5.2
1983	5	5.2
1984	8	5.2
1985	2	5.2
1986	5	5.2
1987	6	5.2
1988	5	5.2
1989	7	5.2
1990	3	6.3
1991	5	6.3
1992	13	6.3
1995	7	6.3
1996	1	6.3
1997	7	6.3
1998	6	6.3
1999	8	6.3
2000	6	5.1
2001	11	5.1
2003	3	5.1
2004	2	5.1
2005	4	5.1
2006	4	5.1
2007	8	5.1
2008	3	5.1
2010	5	4.7
2011	7	4.7
2012	4	4.7
2013	5	4.7
2014	7	4.7
2016	4	4.7
2018	1	4.7
2020	8	4.8
2021	3	4.8
2022	8	4.8
2024	3	4.8
2025	3	4.8
2026	4	4.8

For each year, a bar from the first to the last day at Iron Knob meeting 10 mm (0.39 in).

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

Every Fixed Threshold

Fixed thresholds at Iron Knob
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
10 mm (0.39 in): Days with 10 mm or more rain	97	13	1917	4
25 mm (0.98 in): Days with 25 mm or more rain	53	5	1973	1
50 mm (1.97 in): Days with 50 mm or more rain	19	3	1921	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1911.

Download the Data

Data for Iron Knob 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 2026-10-16 (16 October 2026). Threshold counts are computed by this site.

Data as of 2026-10-16. Last revised 16 October 2026 (2026-10-16).

Iron Knob Threshold Days by Year

Key Facts for Iron Knob Thresholds

Days with 10 mm (0.39 in) or more of precipitation

Every Fixed Threshold

Download the Data

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