Dover Threshold Days by Year (USC00332270)

15 fixed thresholds counted per year at Dover (USC00332270): 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 38 years, most in 1934 with 98.
Dover: days with a maximum temperature at or below 0 C (32 F) in 38 years, most in 1904 with 55.
Dover: days with a maximum temperature at or above 90 F (32.2 C) in 37 years, most in 1931 with 62.
Dover: nights with a minimum temperature at or below 0 C (32 F) in 36 years, most in 1926 with 158.
15 fixed thresholds have at least one qualifying day at Dover.

Days at or above 30 C (86 F)

38 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 98 in 1934.

Days at or above 30 C (86 F) per year at Dover
Year	Days	Decade average
1894	71	55
1896	45	55
1897	42	55
1898	54	55
1899	63	55
1900	67	40
1901	52	40
1902	37	40
1903	36	40
1904	19	40
1905	33	40
1906	44	40
1907	25	40
1908	57	40
1909	30	40
1910	38	31.3
1911	63	31.3
1912	32	31.3
1916	26	31.3
1917	12	31.3
1918	22	31.3
1919	26	31.3
1920	7	40.6
1921	13	40.6
1922	41	40.6
1923	59	40.6
1924	34	40.6
1925	64	40.6
1926	46	40.6
1927	36	40.6
1928	51	40.6
1929	55	40.6
1931	81	73.7
1932	87	73.7
1933	86	73.7
1934	98	73.7
1935	27	73.7
1936	63	73.7

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
1894	1894-05-10	1894-09-15
1896	1896-04-12	1896-09-14
1897	1897-06-12	1897-10-15
1898	1898-05-22	1898-10-03
1899	1899-04-29	1899-09-17
1900	1900-05-13	1900-10-06
1901	1901-06-05	1901-09-07
1902	1902-04-22	1902-08-31
1903	1903-05-17	1903-09-16
1904	1904-05-25	1904-09-29
1905	1905-05-04	1905-08-30
1906	1906-05-15	1906-09-19
1907	1907-06-17	1907-08-20
1908	1908-05-25	1908-09-25
1909	1909-06-20	1909-08-27
1910	1910-06-17	1910-09-05
1911	1911-05-10	1911-09-25
1912	1912-05-23	1912-09-10
1916	1916-07-12	1916-09-08
1917	1917-06-27	1917-08-08
1918	1918-05-27	1918-08-25
1919	1919-05-31	1919-09-10
1920	1920-06-11	1920-07-31
1921	1921-06-25	1921-09-03
1922	1922-05-25	1922-10-07
1923	1923-05-27	1923-10-12
1924	1924-05-07	1924-09-02
1925	1925-04-24	1925-09-21
1926	1926-05-03	1926-10-05
1927	1927-05-10	1927-10-03
1928	1928-05-05	1928-10-14
1929	1929-04-07	1929-09-29
1931	1931-04-19	1931-09-22
1932	1932-05-06	1932-09-22
1933	1933-05-01	1933-09-25
1934	1934-05-04	1934-09-26
1935	1935-06-14	1935-09-18
1936	1936-05-07	1936-09-23

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	38	98	1934	63
35 C (95 F): Days	26	34	1933	11
40 C (104 F): Days	2	1	1933	1
90 F (32.2 C): Days	37	62	1931	36
100 F (37.8 C): Days	11	12	1934	4
0 C (32 F): Ice days (max	38	55	1904	36
0 C (32 F): Frost days (min	36	158	1926	135
-10 C (14 F): Days with min	36	47	1904	31
-20 C (-4 F): Days with min	26	14	1917	9
-30 C (-22 F): Days with min	3	1	1899	1
20 C (68 F): Tropical nights (min	36	26	1916	25
10 mm (0.39 in): Days with 10 mm or more rain	16	44	1899	34
25 mm (0.98 in): Days with 25 mm or more rain	16	15	1905	9
50 mm (1.97 in): Days with 50 mm or more rain	7	5	1905	2
10 cm (3.9 in): Days with 10 cm or more snowfall	1	1	1934	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 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 (USC00332270)

Key Facts for Dover Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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