Dover Threshold Days by Year (USC00282340)

15 fixed thresholds counted per year at Dover (USC00282340): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Dover Thresholds

Dover: days with a maximum temperature at or above 30 C (86 F) in 49 years, most in 1900 with 66.
Dover: days with a maximum temperature at or below 0 C (32 F) in 49 years, most in 1904 with 72.
Dover: nights with a minimum temperature at or below 0 C (32 F) in 49 years, most in 1904 with 162.
Dover: nights with a minimum temperature at or below -10 C (14 F) in 49 years, most in 1904 with 53.
15 fixed thresholds have at least one qualifying day at Dover.

Days at or above 30 C (86 F)

49 years with a qualifying day

Days per year at Dover with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 66 in 1900.

Days at or above 30 C (86 F) per year at Dover
Year	Days	Decade average
1893	37	42.9
1894	38	42.9
1895	54	42.9
1896	45	42.9
1897	34	42.9
1898	50	42.9
1899	42	42.9
1900	66	26.4
1901	41	26.4
1902	20	26.4
1903	21	26.4
1904	6	26.4
1905	18	26.4
1906	20	26.4
1907	21	26.4
1908	28	26.4
1909	23	26.4
1910	22	24.4
1911	30	24.4
1912	24	24.4
1913	29	24.4
1914	23	24.4
1915	27	24.4
1916	21	24.4
1917	18	24.4
1918	28	24.4
1919	22	24.4
1920	20	27.4
1921	27	27.4
1922	28	27.4
1923	39	27.4
1924	24	27.4
1926	23	27.4
1927	18	27.4
1928	31	27.4
1929	37	27.4
1930	39	31.6
1931	39	31.6
1932	47	31.6
1933	28	31.6
1934	30	31.6
1935	29	31.6
1936	38	31.6
1937	22	31.6
1938	18	31.6
1939	26	31.6
1940	14	24
1941	31	24
1943	27	24

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

First to last qualifying date each year at Dover
Year	First date	Last date
1893	1893-05-21	1893-08-27
1894	1894-05-02	1894-09-10
1895	1895-04-25	1895-09-26
1896	1896-04-16	1896-09-10
1897	1897-06-25	1897-10-16
1898	1898-05-20	1898-09-18
1899	1899-05-01	1899-09-08
1900	1900-05-13	1900-10-06
1901	1901-05-24	1901-09-15
1902	1902-04-22	1902-09-02
1903	1903-04-29	1903-09-14
1904	1904-05-25	1904-07-19
1905	1905-06-18	1905-09-30
1906	1906-05-18	1906-09-21
1907	1907-05-14	1907-08-20
1908	1908-05-27	1908-08-14
1909	1909-06-21	1909-08-25
1910	1910-06-20	1910-09-06
1911	1911-05-11	1911-08-23
1912	1912-05-21	1912-09-10
1913	1913-05-02	1913-08-18
1914	1914-05-20	1914-09-23
1915	1915-04-25	1915-09-17
1916	1916-07-07	1916-09-14
1917	1917-06-21	1917-08-21
1918	1918-05-06	1918-08-24
1919	1919-05-05	1919-09-08
1920	1920-05-28	1920-09-24
1921	1921-05-27	1921-08-30
1922	1922-06-07	1922-10-06
1923	1923-04-21	1923-09-03
1924	1924-06-21	1924-09-02
1926	1926-06-30	1926-08-29
1927	1927-04-20	1927-10-02
1928	1928-05-04	1928-10-12
1929	1929-04-07	1929-09-04
1930	1930-05-05	1930-09-16
1931	1931-05-16	1931-09-22
1932	1932-05-16	1932-09-05
1933	1933-05-26	1933-08-26
1934	1934-05-05	1934-08-20
1935	1935-04-27	1935-08-17
1936	1936-05-08	1936-09-08
1937	1937-05-31	1937-09-04
1938	1938-04-28	1938-08-21
1939	1939-04-25	1939-09-16
1940	1940-06-04	1940-08-06
1941	1941-04-20	1941-10-06
1943	1943-05-08	1943-09-07

Every Fixed Threshold

Fixed thresholds at Dover
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	49	66	1900	27
35 C (95 F): Days	32	13	1900	1
90 F (32.2 C): Days	48	38	1900	5
100 F (37.8 C): Days	10	3	1896	3
0 C (32 F): Ice days (max	49	72	1904	27
0 C (32 F): Frost days (min	49	162	1904	139
-10 C (14 F): Days with min	49	53	1904	37
-20 C (-4 F): Days with min	27	6	1918	3
20 C (68 F): Tropical nights (min	49	28	1898	14
25 C (77 F): Days with min	5	1	1896	1
10 mm (0.39 in): Days with 10 mm or more rain	43	49	1899	37
25 mm (0.98 in): Days with 25 mm or more rain	43	25	1903	13
50 mm (1.97 in): Days with 50 mm or more rain	40	7	1901	2
100 mm (3.94 in): Days with 100 mm or more rain	9	2	1903	1
10 cm (3.9 in): Days with 10 cm or more snowfall	3	7	1893	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1893.

Download the Data

Data for Dover 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).

Dover Threshold Days by Year (USC00282340)

Key Facts for Dover Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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