Byzantium Threshold Days by Year

4 fixed thresholds counted per year at Byzantium (ASN00044017): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Byzantium Thresholds

Byzantium: days with 10 mm (0.39 in) or more of precipitation in 69 years, most in 1950 with 36.
Byzantium: days with 25 mm (0.98 in) or more of precipitation in 65 years, most in 1950 with 15.
Byzantium: days with 50 mm (1.97 in) or more of precipitation in 35 years, most in 1963 with 5.
Byzantium: days with 100 mm (3.94 in) or more of precipitation in 5 years, most in 1941 with 1.
4 fixed thresholds have at least one qualifying day at Byzantium.

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

69 years with a qualifying day

Days per year at Byzantium with 10 mm (0.39 in) or more of precipitation, with the decade average as a line. The most was 36 in 1950.

Days with 10 mm (0.39 in) or more of precipitation per year at Byzantium
Year	Days	Decade average
1934	16	12.5
1935	11	12.5
1936	13	12.5
1937	12	12.5
1938	8	12.5
1939	15	12.5
1940	11	13.1
1941	20	13.1
1942	13	13.1
1943	13	13.1
1944	8	13.1
1945	6	13.1
1946	9	13.1
1947	20	13.1
1948	13	13.1
1949	18	13.1
1950	36	19.2
1951	13	19.2
1952	14	19.2
1953	14	19.2
1954	23	19.2
1955	22	19.2
1956	28	19.2
1957	10	19.2
1958	13	19.2
1959	19	19.2
1960	16	15.1
1961	18	15.1
1962	18	15.1
1963	20	15.1
1964	13	15.1
1965	9	15.1
1966	13	15.1
1967	11	15.1
1968	14	15.1
1969	19	15.1
1970	11	17.5
1971	19	17.5
1972	13	17.5
1973	22	17.5
1974	16	17.5
1975	20	17.5
1976	21	17.5
1977	19	17.5
1978	26	17.5
1979	8	17.5
1980	10	15.5
1981	12	15.5
1982	12	15.5
1983	28	15.5
1984	14	15.5
1985	11	15.5
1986	15	15.5
1987	18	15.5
1988	17	15.5
1989	18	15.5
1990	21	16.5
1991	12	16.5
1992	9	16.5
1994	13	16.5
1995	17	16.5
1996	18	16.5
1997	19	16.5
1999	23	16.5
2005	3	6.2
2006	8	6.2
2007	4	6.2
2008	7	6.2
2009	9	6.2

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

First to last qualifying date each year at Byzantium
Year	First date	Last date
1934	1934-01-28	1934-11-26
1935	1935-06-30	1935-12-29
1936	1936-01-09	1936-12-31
1937	1937-01-11	1937-11-20
1938	1938-01-24	1938-11-05
1939	1939-01-18	1939-08-02
1940	1940-01-31	1940-12-31
1941	1941-01-04	1941-12-30
1942	1942-02-14	1942-12-30
1943	1943-01-21	1943-12-22
1944	1944-05-23	1944-11-23
1945	1945-04-26	1945-12-07
1946	1946-01-05	1946-12-05
1947	1947-02-11	1947-12-11
1948	1948-01-02	1948-12-31
1949	1949-01-16	1949-11-21
1950	1950-01-18	1950-12-03
1951	1951-01-08	1951-10-06
1952	1952-02-19	1952-12-31
1953	1953-01-07	1953-11-27
1954	1954-01-01	1954-12-13
1955	1955-01-09	1955-12-19
1956	1956-01-20	1956-12-15
1957	1957-01-10	1957-12-31
1958	1958-01-01	1958-12-31
1959	1959-01-09	1959-12-08
1960	1960-01-22	1960-12-23
1961	1961-02-12	1961-12-19
1962	1962-01-01	1962-12-29
1963	1963-01-09	1963-12-09
1964	1964-01-14	1964-11-13
1965	1965-01-07	1965-12-11
1966	1966-01-07	1966-12-31
1967	1967-01-02	1967-12-29
1968	1968-01-05	1968-12-22
1969	1969-01-10	1969-12-23
1970	1970-01-16	1970-11-12
1971	1971-01-18	1971-12-27
1972	1972-01-29	1972-12-20
1973	1973-01-13	1973-12-31
1974	1974-01-08	1974-11-18
1975	1975-01-03	1975-12-30
1976	1976-01-14	1976-11-20
1977	1977-01-23	1977-12-19
1978	1978-01-17	1978-12-27
1979	1979-01-17	1979-11-13
1980	1980-02-06	1980-12-06
1981	1981-01-17	1981-12-18
1982	1982-01-02	1982-12-28
1983	1983-01-03	1983-12-29
1984	1984-01-01	1984-11-05
1985	1985-02-20	1985-12-08
1986	1986-01-05	1986-11-30
1987	1987-01-01	1987-12-02
1988	1988-01-05	1988-12-27
1989	1989-01-05	1989-11-14
1990	1990-01-15	1990-12-08
1991	1991-01-06	1991-12-13
1992	1992-02-05	1992-12-13
1994	1994-02-12	1994-12-25
1995	1995-01-18	1995-12-04
1996	1996-01-02	1996-12-18
1997	1997-01-13	1997-12-10
1999	1999-01-01	1999-12-18
2005	2005-01-21	2005-11-01
2006	2006-01-14	2006-12-31
2007	2007-06-26	2007-11-01
2008	2008-02-05	2008-12-15
2009	2009-01-05	2009-12-23

Every Fixed Threshold

Fixed thresholds at Byzantium
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	69	36	1950	9
25 mm (0.98 in): Days with 25 mm or more rain	65	15	1950	2
50 mm (1.97 in): Days with 50 mm or more rain	35	5	1963	1
100 mm (3.94 in): Days with 100 mm or more rain	5	1	1941	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1934.

Download the Data

Data for Byzantium 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 2025-12-31. Last revised 31 December 2025 (2025-12-31).

Byzantium Threshold Days by Year

Key Facts for Byzantium Thresholds

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

Every Fixed Threshold

Download the Data

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