Corona Threshold Days by Year (USC00042031)

14 fixed thresholds counted per year at Corona (USC00042031): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Corona Thresholds

Corona: nights with a minimum temperature at or below 0 C (32 F) in 72 years, most in 1945 with 31.
Corona: days with a maximum temperature at or above 30 C (86 F) in 71 years, most in 1917 with 141.
Corona: days with a maximum temperature at or above 35 C (95 F) in 71 years, most in 1917 with 79.
Corona: days with a maximum temperature at or above 90 F (32.2 C) in 71 years, most in 1917 with 119.
14 fixed thresholds have at least one qualifying day at Corona.

Days at or above 30 C (86 F)

71 years with a qualifying day

Days per year at Corona with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 141 in 1917.

Days at or above 30 C (86 F) per year at Corona
Year	Days	Decade average
1914	107	112.8
1915	108	112.8
1916	67	112.8
1917	141	112.8
1918	132	112.8
1919	122	112.8
1920	102	126
1921	133	126
1923	124	126
1924	141	126
1925	131	126
1926	125	126
1927	127	126
1928	125	126
1929	126	126
1930	117	112
1931	136	112
1932	103	112
1933	101	112
1934	109	112
1935	87	112
1936	125	112
1937	125	112
1938	108	112
1939	109	112
1940	114	103.9
1941	91	103.9
1942	94	103.9
1943	122	103.9
1944	79	103.9
1945	103	103.9
1946	123	103.9
1947	116	103.9
1949	93	103.9
1950	74	105.3
1951	72	105.3
1952	123	105.3
1953	116	105.3
1954	107	105.3
1956	106	105.3
1957	106	105.3
1958	130	105.3
1959	114	105.3
1960	128	110.9
1961	102	110.9
1962	105	110.9
1963	97	110.9
1964	105	110.9
1965	108	110.9
1966	121	110.9
1967	115	110.9
1968	123	110.9
1969	105	110.9
1970	119	112
1971	122	112
1972	97	112
1973	97	112
1974	115	112
1975	102	112
1976	108	112
1977	116	112
1978	134	112
1979	110	112
1980	128	117.5
1981	138	117.5
1982	91	117.5
1983	104	117.5
1984	137	117.5
1985	117	117.5
1986	120	117.5
1987	105	117.5

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

First to last qualifying date each year at Corona
Year	First date	Last date
1914	1914-03-08	1914-11-25
1915	1915-04-01	1915-11-19
1916	1916-03-09	1916-10-26
1917	1917-03-26	1917-11-22
1918	1918-01-01	1918-11-01
1919	1919-04-01	1919-11-16
1920	1920-01-17	1920-11-14
1921	1921-02-11	1921-12-10
1923	1923-01-07	1923-11-25
1924	1924-02-12	1924-11-29
1925	1925-02-26	1925-10-20
1926	1926-03-13	1926-11-20
1927	1927-03-23	1927-12-03
1928	1928-03-18	1928-11-04
1929	1929-05-02	1929-11-19
1930	1930-02-17	1930-11-09
1931	1931-03-04	1931-11-05
1932	1932-02-28	1932-11-19
1933	1933-04-15	1933-11-26
1934	1934-03-10	1934-11-06
1935	1935-05-06	1935-10-28
1936	1936-03-12	1936-11-19
1937	1937-04-15	1937-10-26
1938	1938-04-09	1938-12-09
1939	1939-03-16	1939-11-01
1940	1940-04-10	1940-10-20
1941	1941-05-06	1941-11-07
1942	1942-04-19	1942-11-01
1943	1943-02-14	1943-10-24
1944	1944-05-03	1944-10-27
1945	1945-04-05	1945-11-04
1946	1946-03-08	1946-10-25
1947	1947-03-14	1947-10-31
1949	1949-04-10	1949-11-06
1950	1950-04-17	1950-11-22
1951	1951-04-12	1951-10-19
1952	1952-04-03	1952-11-06
1953	1953-01-10	1953-12-14
1954	1954-02-04	1954-11-26
1956	1956-04-20	1956-12-29
1957	1957-02-12	1957-10-27
1958	1958-04-12	1958-12-11
1959	1959-03-12	1959-11-24
1960	1960-03-18	1960-10-22
1961	1961-02-21	1961-10-25
1962	1962-01-07	1962-11-08
1963	1963-02-03	1963-11-10
1964	1964-04-09	1964-11-30
1965	1965-04-19	1965-11-04
1966	1966-03-30	1966-11-02
1967	1967-05-07	1967-11-13
1968	1968-02-24	1968-11-23
1969	1969-03-26	1969-11-02
1970	1970-04-05	1970-10-30
1971	1971-01-17	1971-11-03
1972	1972-03-04	1972-10-07
1973	1973-05-02	1973-11-11
1974	1974-04-14	1974-11-24
1975	1975-01-14	1975-12-09
1976	1976-01-16	1976-11-17
1977	1977-02-12	1977-11-28
1978	1978-03-17	1978-11-08
1979	1979-03-07	1979-12-06
1980	1980-02-26	1980-12-29
1981	1981-02-16	1981-11-08
1982	1982-04-19	1982-10-23
1983	1983-04-16	1983-11-03
1984	1984-03-19	1984-11-01
1985	1985-02-15	1985-11-06
1986	1986-01-18	1986-11-12
1987	1987-01-26	1987-10-27

Every Fixed Threshold

Fixed thresholds at Corona
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	71	141	1917	105
35 C (95 F): Days	71	79	1917	27
40 C (104 F): Days	61	14	1929	4
45 C (113 F): Days	3	3	1917	1
90 F (32.2 C): Days	71	119	1917	70
100 F (37.8 C): Days	70	39	1924	10
110 F (43.3 C): Days	19	4	1917	1
0 C (32 F): Frost days (min	72	31	1945	12
20 C (68 F): Tropical nights (min	51	24	1984	2
25 C (77 F): Days with min	1	1	1984	1
10 mm (0.39 in): Days with 10 mm or more rain	60	26	1978	11
25 mm (0.98 in): Days with 25 mm or more rain	55	9	1980	1
50 mm (1.97 in): Days with 50 mm or more rain	23	5	1921	1
100 mm (3.94 in): Days with 100 mm or more rain	3	1	1926	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1914.

Download the Data

Data for Corona 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).

Corona Threshold Days by Year (USC00042031)

Key Facts for Corona Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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