Grafton Threshold Days by Year (USC00323594)

19 fixed thresholds counted per year at Grafton (USC00323594): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Grafton Thresholds

Grafton: nights with a minimum temperature at or below 0 C (32 F) in 95 years, most in 1917 with 226.
Grafton: nights with a minimum temperature at or below -10 C (14 F) in 95 years, most in 1950 with 134.
Grafton: nights with a minimum temperature at or below -20 C (-4 F) in 95 years, most in 1916 with 86.
Grafton: nights with a minimum temperature at or below -30 C (-22 F) in 91 years, most in 1917 with 45.
19 fixed thresholds have at least one qualifying day at Grafton.

Days at or above 30 C (86 F)

85 years with a qualifying day

Days per year at Grafton with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 75 in 1976.

Days at or above 30 C (86 F) per year at Grafton
Year	Days	Decade average
1894	55	23.5
1895	4	23.5
1896	17	23.5
1897	18	23.5
1906	21	21
1911	14	23.1
1913	31	23.1
1914	28	23.1
1915	14	23.1
1916	24	23.1
1917	29	23.1
1918	14	23.1
1919	31	23.1
1920	35	25
1921	25	25
1922	33	25
1923	34	25
1924	10	25
1925	25	25
1926	24	25
1927	14	25
1928	17	25
1929	33	25
1930	40	49.9
1931	50	49.9
1932	46	49.9
1933	54	49.9
1934	67	49.9
1935	34	49.9
1936	61	49.9
1937	43	49.9
1938	49	49.9
1939	55	49.9
1940	40	29.7
1941	37	29.7
1942	9	29.7
1943	35	29.7
1944	25	29.7
1945	18	29.7
1946	35	29.7
1947	30	29.7
1949	38	29.7
1950	19	27.8
1951	18	27.8
1952	46	27.8
1953	35	27.8
1954	23	27.8
1955	37	27.8
1956	13	27.8
1957	27	27.8
1958	22	27.8
1959	38	27.8
1960	29	30.2
1961	54	30.2
1962	14	30.2
1963	44	30.2
1964	27	30.2
1965	18	30.2
1966	33	30.2
1967	34	30.2
1968	19	30.2
1970	50	35.3
1971	20	35.3
1972	23	35.3
1973	28	35.3
1974	27	35.3
1975	17	35.3
1976	75	35.3
1977	37	35.3
1978	48	35.3
1979	28	35.3
1980	54	32.8
1981	25	32.8
1985	15	32.8
1989	37	32.8
1990	24	25.1
1991	32	25.1
1992	17	25.1
1994	17	25.1
1995	36	25.1
1996	35	25.1
1998	23	25.1
1999	17	25.1
2003	28	19.5
2004	11	19.5

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

First to last qualifying date each year at Grafton
Year	First date	Last date
1894	1894-06-02	1894-09-06
1895	1895-08-13	1895-09-02
1896	1896-05-06	1896-08-28
1897	1897-05-04	1897-09-29
1906	1906-05-11	1906-09-09
1911	1911-05-07	1911-08-20
1913	1913-05-26	1913-09-05
1914	1914-05-27	1914-10-02
1915	1915-08-05	1915-09-06
1916	1916-07-05	1916-08-28
1917	1917-05-16	1917-09-18
1918	1918-05-01	1918-08-26
1919	1919-05-27	1919-09-06
1920	1920-06-07	1920-10-06
1921	1921-06-17	1921-09-01
1922	1922-06-03	1922-10-03
1923	1923-05-25	1923-09-15
1924	1924-06-16	1924-08-29
1925	1925-05-19	1925-09-03
1926	1926-04-29	1926-09-01
1927	1927-06-19	1927-09-13
1928	1928-05-07	1928-09-07
1929	1929-05-25	1929-09-23
1930	1930-05-03	1930-09-23
1931	1931-05-14	1931-09-11
1932	1932-05-13	1932-09-09
1933	1933-06-01	1933-09-09
1934	1934-04-29	1934-10-10
1935	1935-07-01	1935-09-16
1936	1936-05-11	1936-10-08
1937	1937-05-28	1937-09-22
1938	1938-06-05	1938-09-27
1939	1939-05-05	1939-09-19
1940	1940-05-11	1940-09-06
1941	1941-05-03	1941-09-20
1942	1942-07-09	1942-09-06
1943	1943-06-18	1943-10-08
1944	1944-05-23	1944-08-20
1945	1945-06-21	1945-08-27
1946	1946-05-26	1946-08-16
1947	1947-04-28	1947-09-05
1949	1949-04-29	1949-08-25
1950	1950-06-04	1950-09-07
1951	1951-05-23	1951-08-02
1952	1952-04-19	1952-09-28
1953	1953-05-06	1953-10-01
1954	1954-06-13	1954-09-01
1955	1955-05-13	1955-09-06
1956	1956-05-21	1956-08-21
1957	1957-07-02	1957-08-11
1958	1958-05-12	1958-08-19
1959	1959-05-24	1959-09-09
1960	1960-07-07	1960-09-20
1961	1961-05-20	1961-09-04
1962	1962-06-26	1962-09-02
1963	1963-05-30	1963-10-04
1964	1964-05-20	1964-08-06
1965	1965-05-13	1965-08-23
1966	1966-05-21	1966-09-13
1967	1967-06-28	1967-09-07
1968	1968-05-01	1968-09-15
1970	1970-05-17	1970-09-20
1971	1971-06-03	1971-09-04
1972	1972-05-16	1972-08-30
1973	1973-06-01	1973-08-31
1974	1974-06-19	1974-08-25
1975	1975-07-04	1975-08-24
1976	1976-05-09	1976-10-01
1977	1977-04-25	1977-08-09
1978	1978-05-22	1978-09-11
1979	1979-06-13	1979-09-17
1980	1980-04-18	1980-09-08
1981	1981-05-21	1981-09-11
1985	1985-04-28	1985-08-09
1989	1989-05-15	1989-09-30
1990	1990-04-21	1990-09-11
1991	1991-05-12	1991-09-08
1992	1992-04-30	1992-10-01
1994	1994-05-17	1994-09-11
1995	1995-05-30	1995-09-12
1996	1996-06-09	1996-09-05
1998	1998-05-27	1998-09-17
1999	1999-05-28	1999-09-01
2003	2003-06-15	2003-09-08
2004	2004-06-29	2004-09-20

Every Fixed Threshold

Fixed thresholds at Grafton
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	85	75	1976	11
35 C (95 F): Days	77	23	1936	2
40 C (104 F): Days	8	7	1936	2
90 F (32.2 C): Days	85	42	1936	1
100 F (37.8 C): Days	33	11	1936	1
0 C (32 F): Ice days (max	85	129	1955	85
0 C (32 F): Frost days (min	95	226	1917	161
-10 C (14 F): Days with min	95	134	1950	75
-20 C (-4 F): Days with min	95	86	1916	37
-30 C (-22 F): Days with min	91	45	1917	6
-40 C (-40 F): Days with min	9	3	1917	2
20 C (68 F): Tropical nights (min	72	16	1995	5
25 C (77 F): Days with min	4	1	1945	2
10 mm (0.39 in): Days with 10 mm or more rain	77	22	1944	18
25 mm (0.98 in): Days with 25 mm or more rain	71	7	1964	6
50 mm (1.97 in): Days with 50 mm or more rain	28	3	2009	3
100 mm (3.94 in): Days with 100 mm or more rain	6	1	1897	1
10 cm (3.9 in): Days with 10 cm or more snowfall	22	9	1949	4
25 cm (9.8 in): Days with 25 cm or more snowfall	4	2	1955	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1894.

Download the Data

Data for Grafton 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).

Grafton Threshold Days by Year (USC00323594)

Key Facts for Grafton Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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