Santa Rosa Threshold Days by Year (USC00047965)

16 fixed thresholds counted per year at Santa Rosa (USC00047965): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Santa Rosa Thresholds

Santa Rosa: nights with a minimum temperature at or below 0 C (32 F) in 111 years, most in 1919 with 91.
Santa Rosa: days with a maximum temperature at or above 30 C (86 F) in 107 years, most in 1936 with 94.
Santa Rosa: days with a maximum temperature at or above 90 F (32.2 C) in 107 years, most in 1936 with 57.
Santa Rosa: days with a maximum temperature at or above 35 C (95 F) in 106 years, most in 2024 with 34.
16 fixed thresholds have at least one qualifying day at Santa Rosa.

Days at or above 30 C (86 F)

107 years with a qualifying day

Days per year at Santa Rosa with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 94 in 1936.

Days at or above 30 C (86 F) per year at Santa Rosa
Year	Days	Decade average
1903	53	41.1
1904	42	41.1
1905	34	41.1
1906	49	41.1
1907	25	41.1
1908	42	41.1
1909	43	41.1
1910	47	43.8
1911	31	43.8
1912	35	43.8
1913	50	43.8
1915	65	43.8
1916	45	43.8
1917	48	43.8
1918	34	43.8
1919	39	43.8
1920	21	45.1
1921	49	45.1
1922	41	45.1
1923	38	45.1
1924	47	45.1
1925	33	45.1
1926	82	45.1
1927	47	45.1
1928	34	45.1
1929	59	45.1
1930	38	58.9
1931	74	58.9
1932	44	58.9
1933	41	58.9
1934	50	58.9
1935	56	58.9
1936	94	58.9
1937	64	58.9
1938	52	58.9
1939	76	58.9
1940	29	45.7
1941	46	45.7
1942	42	45.7
1943	48	45.7
1944	40	45.7
1945	60	45.7
1946	44	45.7
1947	60	45.7
1948	43	45.7
1949	45	45.7
1950	50	50
1951	33	50
1952	55	50
1953	48	50
1954	49	50
1955	57	50
1956	37	50
1957	56	50
1958	50	50
1959	65	50
1960	51	57.5
1961	62	57.5
1962	42	57.5
1963	45	57.5
1964	54	57.5
1965	41	57.5
1966	69	57.5
1967	80	57.5
1968	62	57.5
1969	69	57.5
1970	66	59.8
1971	65	59.8
1972	50	59.8
1973	57	59.8
1974	66	59.8
1975	48	59.8
1976	70	59.8
1977	56	59.8
1980	31	37.4
1981	52	37.4
1982	47	37.4
1983	54	37.4
1984	51	37.4
1985	22	37.4
1986	9	37.4
1987	21	37.4
1988	48	37.4
1989	39	37.4
1990	32	35.8
1991	32	35.8
1992	32	35.8
1993	51	35.8
1994	25	35.8
1995	33	35.8
1996	46	35.8
1997	40	35.8
1998	31	35.8
2003	44	37.6
2004	47	37.6
2005	28	37.6
2006	38	37.6
2007	31	37.6
2018	62	70
2019	78	70
2020	91	69.9
2021	71	69.9
2022	69	69.9
2023	56	69.9
2024	80	69.9
2025	52	69.9
2026	70	69.9

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

First to last qualifying date each year at Santa Rosa
Year	First date	Last date
1903	1903-05-08	1903-10-19
1904	1904-04-11	1904-10-04
1905	1905-05-15	1905-10-12
1906	1906-06-18	1906-10-27
1907	1907-04-18	1907-10-14
1908	1908-04-10	1908-10-07
1909	1909-04-30	1909-10-10
1910	1910-04-23	1910-10-25
1911	1911-05-20	1911-10-19
1912	1912-05-31	1912-10-17
1913	1913-04-23	1913-10-25
1915	1915-03-21	1915-10-28
1916	1916-04-13	1916-09-28
1917	1917-06-12	1917-10-26
1918	1918-06-01	1918-10-29
1919	1919-05-27	1919-10-12
1920	1920-05-18	1920-09-29
1921	1921-04-27	1921-10-21
1922	1922-05-02	1922-09-25
1923	1923-02-27	1923-10-20
1924	1924-04-05	1924-10-03
1925	1925-05-02	1925-10-26
1926	1926-03-21	1926-11-07
1927	1927-04-23	1927-10-19
1928	1928-04-07	1928-10-08
1929	1929-03-03	1929-11-04
1930	1930-03-24	1930-11-11
1931	1931-04-09	1931-11-06
1932	1932-05-24	1932-11-17
1933	1933-04-13	1933-10-23
1934	1934-05-10	1934-10-10
1935	1935-05-04	1935-10-27
1936	1936-04-11	1936-10-23
1937	1937-05-02	1937-10-23
1938	1938-04-18	1938-10-25
1939	1939-04-05	1939-10-30
1940	1940-04-12	1940-10-18
1941	1941-05-10	1941-10-16
1942	1942-05-19	1942-10-22
1943	1943-05-18	1943-10-14
1944	1944-05-02	1944-10-25
1945	1945-04-22	1945-11-02
1946	1946-04-23	1946-10-25
1947	1947-04-11	1947-10-12
1948	1948-06-21	1948-10-17
1949	1949-05-05	1949-10-30
1950	1950-05-20	1950-11-04
1951	1951-05-15	1951-10-14
1952	1952-03-25	1952-10-06
1953	1953-05-05	1953-10-09
1954	1954-04-17	1954-10-16
1955	1955-05-20	1955-11-11
1956	1956-05-16	1956-09-30
1957	1957-04-04	1957-09-23
1958	1958-04-12	1958-10-30
1959	1959-05-08	1959-11-01
1960	1960-04-05	1960-10-30
1961	1961-04-04	1961-10-18
1962	1962-04-13	1962-10-02
1963	1963-05-17	1963-10-02
1964	1964-04-15	1964-10-23
1965	1965-04-26	1965-10-31
1966	1966-04-01	1966-11-02
1967	1967-05-07	1967-11-02
1968	1968-04-26	1968-10-23
1969	1969-05-05	1969-10-20
1970	1970-03-25	1970-10-10
1971	1971-06-14	1971-10-13
1972	1972-05-01	1972-10-07
1973	1973-05-10	1973-10-17
1974	1974-04-29	1974-10-18
1975	1975-05-12	1975-10-20
1976	1976-05-11	1976-11-04
1977	1977-04-12	1977-10-15
1980	1980-05-19	1980-10-08
1981	1981-04-29	1981-10-02
1982	1982-05-22	1982-10-13
1983	1983-05-17	1983-10-26
1984	1984-05-07	1984-09-29
1985	1985-06-10	1985-10-04
1986	1986-06-09	1986-09-11
1987	1987-05-05	1987-10-18
1988	1988-04-10	1988-10-18
1989	1989-04-05	1989-10-19
1990	1990-05-01	1990-10-12
1991	1991-06-01	1991-10-21
1992	1992-05-09	1992-10-11
1993	1993-06-09	1993-10-28
1994	1994-06-09	1994-10-09
1995	1995-06-23	1995-10-19
1996	1996-03-17	1996-10-08
1997	1997-05-16	1997-11-02
1998	1998-06-16	1998-10-22
2003	2003-05-27	2003-10-29
2004	2004-03-10	2004-10-13
2005	2005-03-10	2005-10-17
2006	2006-05-14	2006-10-22
2007	2007-05-06	2007-10-24
2018	2018-03-29	2018-11-01
2019	2019-04-22	2019-10-25
2020	2020-04-23	2020-10-21
2021	2021-04-18	2021-10-05
2022	2022-03-22	2022-10-20
2023	2023-04-26	2023-10-20
2024	2024-05-09	2024-10-09
2025	2025-05-05	2025-10-07
2026	2026-03-16	2026-10-09

Every Fixed Threshold

Fixed thresholds at Santa Rosa
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	107	94	1936	70
35 C (95 F): Days	106	34	2024	17
40 C (104 F): Days	49	6	1977	2
45 C (113 F): Days	2	1	1913	1
90 F (32.2 C): Days	107	57	1936	43
100 F (37.8 C): Days	85	15	2024	3
110 F (43.3 C): Days	6	2	1971	2
0 C (32 F): Frost days (min	111	91	1919	2
-10 C (14 F): Days with min	1	1	1924	1
20 C (68 F): Tropical nights (min	9	3	1920	1
25 C (77 F): Days with min	1	1	1993	1
10 mm (0.39 in): Days with 10 mm or more rain	98	56	1983	14
25 mm (0.98 in): Days with 25 mm or more rain	98	23	1983	6
50 mm (1.97 in): Days with 50 mm or more rain	72	5	1926	3
100 mm (3.94 in): Days with 100 mm or more rain	16	2	2024	2
10 cm (3.9 in): Days with 10 cm or more snowfall	1	1	1963	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1903.

Download the Data

Data for Santa Rosa 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 2026-10-17. Last revised 17 October 2026 (2026-10-17).

Santa Rosa Threshold Days by Year (USC00047965)

Key Facts for Santa Rosa Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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