Granta Threshold Days by Year (SF000804570)

4 fixed thresholds counted per year at Granta (SF000804570): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Granta Thresholds

Granta: days with 10 mm (0.39 in) or more of precipitation in 67 years, most in 1985 with 38.
Granta: days with 25 mm (0.98 in) or more of precipitation in 67 years, most in 1935 with 12.
Granta: days with 50 mm (1.97 in) or more of precipitation in 49 years, most in 1970 with 4.
Granta: days with 100 mm (3.94 in) or more of precipitation in 8 years, most in 1970 with 2.
4 fixed thresholds have at least one qualifying day at Granta.

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

67 years with a qualifying day

Days per year at Granta with 10 mm (0.39 in) or more of precipitation, with the decade average as a line. The most was 38 in 1985.

Days with 10 mm (0.39 in) or more of precipitation per year at Granta
Year	Days	Decade average
1918	21	18
1919	15	18
1921	26	24.8
1925	27	24.8
1928	20	24.8
1929	26	24.8
1930	26	24.1
1931	21	24.1
1932	23	24.1
1933	21	24.1
1934	24	24.1
1935	23	24.1
1936	22	24.1
1937	25	24.1
1938	34	24.1
1939	22	24.1
1940	22	20.8
1941	16	20.8
1942	27	20.8
1943	26	20.8
1944	23	20.8
1945	20	20.8
1947	19	20.8
1948	21	20.8
1949	13	20.8
1950	25	24
1951	13	24
1952	19	24
1955	25	24
1956	30	24
1957	21	24
1958	24	24
1959	35	24
1960	25	22.2
1961	25	22.2
1962	22	22.2
1963	34	22.2
1965	19	22.2
1966	11	22.2
1967	27	22.2
1968	13	22.2
1969	24	22.2
1970	23	23
1971	24	23
1973	17	23
1974	25	23
1975	25	23
1977	25	23
1979	22	23
1980	13	21.7
1981	22	21.7
1982	14	21.7
1983	14	21.7
1984	25	21.7
1985	38	21.7
1986	24	21.7
1987	15	21.7
1988	26	21.7
1989	26	21.7
1990	23	21.3
1991	22	21.3
1992	14	21.3
1993	20	21.3
1994	23	21.3
1995	22	21.3
1996	23	21.3
1997	23	21.3

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

First to last qualifying date each year at Granta
Year	First date	Last date
1918	1918-01-05	1918-12-23
1919	1919-01-18	1919-10-20
1921	1921-01-05	1921-12-13
1925	1925-01-03	1925-12-28
1928	1928-01-05	1928-12-27
1929	1929-02-03	1929-12-30
1930	1930-01-03	1930-12-15
1931	1931-01-01	1931-12-31
1932	1932-01-01	1932-12-25
1933	1933-01-02	1933-12-29
1934	1934-01-09	1934-12-23
1935	1935-01-03	1935-12-19
1936	1936-01-01	1936-12-30
1937	1937-01-20	1937-12-21
1938	1938-01-12	1938-12-31
1939	1939-01-01	1939-12-26
1940	1940-01-07	1940-12-21
1941	1941-01-20	1941-12-21
1942	1942-01-04	1942-12-21
1943	1943-01-20	1943-12-19
1944	1944-01-01	1944-12-31
1945	1945-01-05	1945-12-04
1947	1947-01-09	1947-12-27
1948	1948-01-03	1948-12-30
1949	1949-01-30	1949-12-11
1950	1950-01-04	1950-12-31
1951	1951-01-06	1951-12-11
1952	1952-01-15	1952-12-16
1955	1955-01-04	1955-12-05
1956	1956-02-09	1956-12-22
1957	1957-01-02	1957-12-28
1958	1958-01-07	1958-12-31
1959	1959-01-01	1959-12-23
1960	1960-01-17	1960-12-30
1961	1961-01-15	1961-11-30
1962	1962-01-08	1962-12-27
1963	1963-01-04	1963-12-29
1965	1965-01-05	1965-12-16
1966	1966-01-07	1966-12-30
1967	1967-01-12	1967-12-10
1968	1968-01-22	1968-12-29
1969	1969-01-09	1969-12-27
1970	1970-01-14	1970-12-19
1971	1971-01-09	1971-10-22
1973	1973-01-30	1973-12-26
1974	1974-01-13	1974-12-24
1975	1975-01-19	1975-12-23
1977	1977-02-06	1977-12-31
1979	1979-01-01	1979-12-25
1980	1980-01-21	1980-12-27
1981	1981-01-10	1981-12-23
1982	1982-02-27	1982-10-31
1983	1983-01-13	1983-12-29
1984	1984-01-01	1984-11-28
1985	1985-01-13	1985-12-20
1986	1986-01-03	1986-12-16
1987	1987-01-18	1987-12-22
1988	1988-02-06	1988-12-29
1989	1989-01-01	1989-12-23
1990	1990-01-06	1990-12-16
1991	1991-01-22	1991-12-31
1992	1992-02-05	1992-12-31
1993	1993-01-08	1993-12-25
1994	1994-01-07	1994-12-24
1995	1995-01-14	1995-12-19
1996	1996-01-12	1996-12-29
1997	1997-01-01	1997-11-28

Every Fixed Threshold

Fixed thresholds at Granta
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	67	38	1985	23
25 mm (0.98 in): Days with 25 mm or more rain	67	12	1935	10
50 mm (1.97 in): Days with 50 mm or more rain	49	4	1970	3
100 mm (3.94 in): Days with 100 mm or more rain	8	2	1970	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1918.

Download the Data

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

Granta Threshold Days by Year (SF000804570)

Key Facts for Granta Thresholds

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

Every Fixed Threshold

Download the Data

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