Vacaville Threshold Days by Year (USC00049200)

16 fixed thresholds counted per year at Vacaville (USC00049200): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Vacaville Thresholds

Vacaville: days with a maximum temperature at or above 30 C (86 F) in 90 years, most in 1992 with 141.
Vacaville: days with a maximum temperature at or above 35 C (95 F) in 90 years, most in 1996 with 76.
Vacaville: days with a maximum temperature at or above 90 F (32.2 C) in 90 years, most in 1992 with 119.
Vacaville: days with a maximum temperature at or above 100 F (37.8 C) in 90 years, most in 1996 with 46.
16 fixed thresholds have at least one qualifying day at Vacaville.

Days at or above 30 C (86 F)

90 years with a qualifying day

Days per year at Vacaville with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 141 in 1992.

Days at or above 30 C (86 F) per year at Vacaville
Year	Days	Decade average
1905	87	94.8
1906	104	94.8
1907	74	94.8
1908	109	94.8
1909	100	94.8
1910	110	94
1911	85	94
1912	99	94
1916	82	94
1920	98	111.9
1921	114	111.9
1922	110	111.9
1923	89	111.9
1924	112	111.9
1925	74	111.9
1926	122	111.9
1927	129	111.9
1928	136	111.9
1929	135	111.9
1930	113	121.8
1931	120	121.8
1932	120	121.8
1933	131	121.8
1934	138	121.8
1935	115	121.8
1936	122	121.8
1937	121	121.8
1938	111	121.8
1939	127	121.8
1940	112	108.5
1941	84	108.5
1942	112	108.5
1943	112	108.5
1944	108	108.5
1945	114	108.5
1946	106	108.5
1947	124	108.5
1948	94	108.5
1949	119	108.5
1950	115	115.6
1951	110	115.6
1952	115	115.6
1953	104	115.6
1954	119	115.6
1955	122	115.6
1956	114	115.6
1957	113	115.6
1958	123	115.6
1959	121	115.6
1960	119	111.6
1961	106	111.6
1962	111	111.6
1963	87	111.6
1964	114	111.6
1965	116	111.6
1966	115	111.6
1967	126	111.6
1968	109	111.6
1969	113	111.6
1970	125	111.9
1971	110	111.9
1972	114	111.9
1973	109	111.9
1974	127	111.9
1975	107	111.9
1976	102	111.9
1977	96	111.9
1979	117	111.9
1981	108	99
1982	75	99
1983	89	99
1984	117	99
1987	106	99
1991	128	117.5
1992	141	117.5
1993	104	117.5
1995	116	117.5
1996	127	117.5
1997	138	117.5
1998	63	117.5
1999	123	117.5
2000	113	122.3
2001	130	122.3
2002	129	122.3
2003	132	122.3
2004	125	122.3
2005	101	122.3
2006	130	122.3
2007	111	122.3
2008	130	122.3

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

First to last qualifying date each year at Vacaville
Year	First date	Last date
1905	1905-05-15	1905-10-28
1906	1906-05-02	1906-11-13
1907	1907-05-14	1907-10-15
1908	1908-04-09	1908-11-07
1909	1909-04-15	1909-10-25
1910	1910-04-17	1910-10-27
1911	1911-04-15	1911-11-02
1912	1912-05-06	1912-10-17
1916	1916-05-01	1916-09-28
1920	1920-04-26	1920-10-03
1921	1921-04-21	1921-10-20
1922	1922-05-01	1922-09-30
1923	1923-05-06	1923-10-20
1924	1924-04-05	1924-10-03
1925	1925-05-02	1925-10-26
1926	1926-04-24	1926-11-06
1927	1927-04-23	1927-10-23
1928	1928-04-29	1928-10-20
1929	1929-03-04	1929-11-12
1930	1930-05-01	1930-10-18
1931	1931-04-16	1931-11-07
1932	1932-05-06	1932-11-18
1933	1933-05-24	1933-10-27
1934	1934-04-05	1934-10-28
1935	1935-04-26	1935-10-25
1936	1936-05-06	1936-10-15
1937	1937-05-02	1937-10-24
1938	1938-05-11	1938-10-13
1939	1939-04-05	1939-10-22
1940	1940-04-13	1940-10-19
1941	1941-05-10	1941-11-05
1942	1942-05-19	1942-10-19
1943	1943-05-10	1943-10-15
1944	1944-05-02	1944-10-28
1945	1945-04-17	1945-10-06
1946	1946-04-22	1946-10-12
1947	1947-04-12	1947-10-04
1948	1948-05-05	1948-10-17
1949	1949-04-11	1949-11-03
1950	1950-04-17	1950-10-14
1951	1951-04-09	1951-10-14
1952	1952-04-17	1952-10-12
1953	1953-04-24	1953-10-09
1954	1954-04-13	1954-10-22
1955	1955-05-10	1955-11-10
1956	1956-05-15	1956-10-06
1957	1957-04-04	1957-09-24
1958	1958-04-21	1958-10-17
1959	1959-04-23	1959-10-25
1960	1960-04-04	1960-10-22
1961	1961-04-03	1961-10-06
1962	1962-04-05	1962-10-01
1963	1963-05-16	1963-10-03
1964	1964-04-13	1964-10-22
1965	1965-04-24	1965-10-26
1966	1966-03-31	1966-10-25
1967	1967-05-15	1967-11-02
1968	1968-03-29	1968-10-26
1969	1969-05-05	1969-10-01
1970	1970-05-02	1970-10-11
1971	1971-05-22	1971-10-14
1972	1972-04-27	1972-10-07
1973	1973-04-25	1973-10-16
1974	1974-05-06	1974-10-19
1975	1975-05-12	1975-10-06
1976	1976-04-30	1976-10-16
1977	1977-04-12	1977-10-15
1979	1979-05-11	1979-10-10
1981	1981-04-21	1981-10-01
1982	1982-05-04	1982-09-13
1983	1983-05-18	1983-10-11
1984	1984-05-07	1984-10-07
1987	1987-04-15	1987-10-18
1991	1991-05-21	1991-10-21
1992	1992-04-25	1992-10-14
1993	1993-04-28	1993-10-26
1995	1995-05-19	1995-10-20
1996	1996-04-25	1996-10-14
1997	1997-04-15	1997-11-01
1998	1998-04-21	1998-10-21
1999	1999-04-16	1999-10-15
2000	2000-04-02	2000-10-08
2001	2001-04-24	2001-10-19
2002	2002-03-29	2002-10-15
2003	2003-05-13	2003-10-28
2004	2004-03-16	2004-10-14
2005	2005-05-21	2005-10-18
2006	2006-04-27	2006-10-23
2007	2007-04-27	2007-10-03
2008	2008-04-12	2008-10-24

Every Fixed Threshold

Fixed thresholds at Vacaville
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	90	141	1992	130
35 C (95 F): Days	90	76	1996	74
40 C (104 F): Days	89	28	1936	16
45 C (113 F): Days	5	3	1961	3
90 F (32.2 C): Days	90	119	1992	108
100 F (37.8 C): Days	90	46	1996	30
110 F (43.3 C): Days	37	10	1950	3
0 C (32 F): Ice days (max	1	1	1932	1
0 C (32 F): Frost days (min	90	72	1932	10
-10 C (14 F): Days with min	1	1	1924	1
20 C (68 F): Tropical nights (min	61	15	2006	8
25 C (77 F): Days with min	7	2	2006	1
10 mm (0.39 in): Days with 10 mm or more rain	87	43	1983	14
25 mm (0.98 in): Days with 25 mm or more rain	86	17	1940	4
50 mm (1.97 in): Days with 50 mm or more rain	64	6	1940	1
100 mm (3.94 in): Days with 100 mm or more rain	16	2	2005	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1905.

Download the Data

Data for Vacaville 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).

Vacaville Threshold Days by Year (USC00049200)

Key Facts for Vacaville Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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