Derry 4 SW Threshold Days by Year (USC00362108)

19 fixed thresholds counted per year at Derry 4 SW (USC00362108): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Derry 4 SW Thresholds

Derry 4 SW: days with 10 mm (0.39 in) or more of precipitation in 97 years, most in 1985 with 57.
Derry 4 SW: days with 25 mm (0.98 in) or more of precipitation in 97 years, most in 1987 with 17.
Derry 4 SW: days with a maximum temperature at or above 30 C (86 F) in 90 years, most in 1900 with 95.
Derry 4 SW: days with a maximum temperature at or below 0 C (32 F) in 90 years, most in 1995 with 43.
19 fixed thresholds have at least one qualifying day at Derry 4 SW.

Days at or above 30 C (86 F)

90 years with a qualifying day

Days per year at Derry 4 SW with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 95 in 1900.

Days at or above 30 C (86 F) per year at Derry 4 SW
Year	Days	Decade average
1898	64	67.5
1899	71	67.5
1900	95	49.7
1902	31	49.7
1903	37	49.7
1904	36	49.7
1905	39	49.7
1906	59	49.7
1907	28	49.7
1908	77	49.7
1909	45	49.7
1910	56	51.4
1911	68	51.4
1912	34	51.4
1913	61	51.4
1914	60	51.4
1915	35	51.4
1916	55	51.4
1917	30	51.4
1918	55	51.4
1919	60	51.4
1920	29	31.1
1921	67	31.1
1922	34	31.1
1923	34	31.1
1924	28	31.1
1925	39	31.1
1926	34	31.1
1927	20	31.1
1928	15	31.1
1929	11	31.1
1930	31	38.9
1932	10	38.9
1933	26	38.9
1934	45	38.9
1935	23	38.9
1936	53	38.9
1937	50	38.9
1938	50	38.9
1939	62	38.9
1940	34	42.1
1941	54	42.1
1942	46	42.1
1943	45	42.1
1944	45	42.1
1945	40	42.1
1946	36	42.1
1947	46	42.1
1948	30	42.1
1949	45	42.1
1950	16	34.3
1951	37	34.3
1952	47	34.3
1953	46	34.3
1954	36	34.3
1955	43	34.3
1957	31	34.3
1958	18	34.3
1964	35	31.2
1965	34	31.2
1966	32	31.2
1967	17	31.2
1968	38	31.2
1970	34	23
1971	16	23
1972	16	23
1979	26	23
1981	15	38.9
1982	28	38.9
1983	57	38.9
1984	23	38.9
1985	33	38.9
1986	39	38.9
1987	53	38.9
1988	62	38.9
1989	40	38.9
1990	12	24.8
1991	57	24.8
1992	9	24.8
1993	14	24.8
1994	24	24.8
1995	35	24.8
1996	15	24.8
1998	18	24.8
1999	39	24.8
2001	21	24
2002	45	24
2003	8	24
2004	5	24
2005	41	24

For each year, a bar from the first to the last day at Derry 4 SW meeting 30 C (86 F).

First to last qualifying date each year at Derry 4 SW
Year	First date	Last date
1898	1898-05-02	1898-10-04
1899	1899-04-19	1899-10-16
1900	1900-04-30	1900-10-23
1902	1902-05-21	1902-08-31
1903	1903-05-16	1903-10-04
1904	1904-05-25	1904-10-19
1905	1905-05-04	1905-09-30
1906	1906-05-15	1906-11-21
1907	1907-06-17	1907-09-20
1908	1908-04-24	1908-10-16
1909	1909-05-09	1909-09-23
1910	1910-04-05	1910-10-18
1911	1911-05-11	1911-09-24
1912	1912-05-22	1912-09-16
1913	1913-04-24	1913-09-25
1914	1914-04-28	1914-10-10
1915	1915-04-24	1915-09-16
1916	1916-05-14	1916-10-09
1917	1917-06-13	1917-08-27
1918	1918-05-12	1918-09-06
1919	1919-05-27	1919-10-04
1920	1920-05-23	1920-09-27
1921	1921-04-05	1921-09-11
1922	1922-05-23	1922-09-15
1923	1923-05-15	1923-09-27
1924	1924-05-06	1924-09-01
1925	1925-04-23	1925-09-20
1926	1926-05-02	1926-10-04
1927	1927-05-09	1927-10-02
1928	1928-06-13	1928-09-10
1929	1929-03-25	1929-09-07
1930	1930-04-11	1930-09-26
1932	1932-05-16	1932-09-03
1933	1933-06-08	1933-09-08
1934	1934-05-19	1934-09-26
1935	1935-06-14	1935-09-25
1936	1936-05-02	1936-09-27
1937	1937-05-22	1937-10-06
1938	1938-04-27	1938-10-18
1939	1939-05-07	1939-10-10
1940	1940-05-19	1940-09-21
1941	1941-04-20	1941-10-07
1942	1942-04-28	1942-09-19
1943	1943-05-06	1943-09-06
1944	1944-05-03	1944-09-04
1945	1945-05-16	1945-09-25
1946	1946-06-11	1946-10-05
1947	1947-05-28	1947-09-21
1948	1948-06-02	1948-09-17
1949	1949-05-04	1949-10-11
1950	1950-06-07	1950-08-28
1951	1951-05-16	1951-10-05
1952	1952-06-06	1952-10-01
1953	1953-05-11	1953-09-30
1954	1954-04-21	1954-09-30
1955	1955-05-21	1955-09-19
1957	1957-04-26	1957-09-15
1958	1958-04-19	1958-09-04
1964	1964-05-19	1964-09-11
1965	1965-05-08	1965-09-22
1966	1966-06-09	1966-09-03
1967	1967-06-10	1967-08-09
1968	1968-06-06	1968-08-24
1970	1970-04-30	1970-09-24
1971	1971-05-19	1971-09-10
1972	1972-06-15	1972-09-17
1979	1979-04-26	1979-09-07
1981	1981-05-25	1981-07-28
1982	1982-05-07	1982-09-15
1983	1983-05-08	1983-09-21
1984	1984-06-14	1984-09-24
1985	1985-04-21	1985-09-21
1986	1986-04-28	1986-09-28
1987	1987-04-23	1987-08-22
1988	1988-05-16	1988-10-02
1989	1989-05-19	1989-09-11
1990	1990-04-27	1990-08-29
1991	1991-05-14	1991-09-19
1992	1992-05-18	1992-08-11
1993	1993-06-09	1993-09-03
1994	1994-06-14	1994-08-13
1995	1995-06-20	1995-09-01
1996	1996-05-10	1996-08-23
1998	1998-05-15	1998-09-26
1999	1999-06-07	1999-09-12
2001	2001-05-04	2001-08-31
2002	2002-04-16	2002-09-10
2003	2003-06-25	2003-08-22
2004	2004-05-23	2004-08-28
2005	2005-06-05	2005-09-22

Every Fixed Threshold

Fixed thresholds at Derry 4 SW
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	90	95	1900	41
35 C (95 F): Days	40	23	1900	1
40 C (104 F): Days	1	1	1911	1
90 F (32.2 C): Days	86	64	1900	14
100 F (37.8 C): Days	8	3	1918	3
0 C (32 F): Ice days (max	90	43	1995	28
0 C (32 F): Frost days (min	75	153	1917	120
-10 C (14 F): Days with min	75	49	1984	31
-20 C (-4 F): Days with min	50	10	1979	2
-30 C (-22 F): Days with min	1	1	1912	1
20 C (68 F): Tropical nights (min	72	28	1898	4
25 C (77 F): Days with min	5	1	1900	1
10 mm (0.39 in): Days with 10 mm or more rain	97	57	1985	43
25 mm (0.98 in): Days with 25 mm or more rain	97	17	1987	17
50 mm (1.97 in): Days with 50 mm or more rain	69	4	1971	1
100 mm (3.94 in): Days with 100 mm or more rain	6	1	1916	1
10 cm (3.9 in): Days with 10 cm or more snowfall	80	8	1902	2
25 cm (9.8 in): Days with 25 cm or more snowfall	21	2	1927	1
50 cm (19.7 in): Days with 50 cm or more snowfall	2	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 1898.

Download the Data

Data for Derry 4 SW 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).

Derry 4 SW Threshold Days by Year (USC00362108)

Key Facts for Derry 4 SW Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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