Alturas Threshold Days by Year (USC00040161)

15 fixed thresholds counted per year at Alturas (USC00040161): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Alturas Thresholds

Alturas: days with 10 mm (0.39 in) or more of precipitation in 90 years, most in 1969 with 17.
Alturas: nights with a minimum temperature at or below 0 C (32 F) in 80 years, most in 1908 with 233.
Alturas: nights with a minimum temperature at or below -10 C (14 F) in 80 years, most in 1917 with 67.
Alturas: days with a maximum temperature at or above 30 C (86 F) in 79 years, most in 1917 with 92.
15 fixed thresholds have at least one qualifying day at Alturas.

Days at or above 30 C (86 F)

79 years with a qualifying day

Days per year at Alturas with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 92 in 1917.

Days at or above 30 C (86 F) per year at Alturas
Year	Days	Decade average
1906	68	58
1907	38	58
1908	70	58
1909	56	58
1910	64	66.6
1911	59	66.6
1912	45	66.6
1913	47	66.6
1914	80	66.6
1915	67	66.6
1916	59	66.6
1917	92	66.6
1918	82	66.6
1919	71	66.6
1932	55	53.7
1933	64	53.7
1935	52	53.7
1936	64	53.7
1938	37	53.7
1939	50	53.7
1940	50	43.3
1943	34	43.3
1944	31	43.3
1945	62	43.3
1946	51	43.3
1947	54	43.3
1948	27	43.3
1949	37	43.3
1950	57	61.9
1951	65	61.9
1952	54	61.9
1954	52	61.9
1955	66	61.9
1956	62	61.9
1957	67	61.9
1958	69	61.9
1959	65	61.9
1960	80	66.7
1961	77	66.7
1962	70	66.7
1963	63	66.7
1964	50	66.7
1965	32	66.7
1966	79	66.7
1967	92	66.7
1968	63	66.7
1969	61	66.7
1970	63	50.2
1971	51	50.2
1972	52	50.2
1973	58	50.2
1975	40	50.2
1976	39	50.2
1977	62	50.2
1978	37	50.2
1979	50	50.2
1980	44	57
1981	70	57
1982	44	57
1983	40	57
1984	66	57
1985	58	57
1986	65	57
1987	63	57
1988	78	57
1989	42	57
1990	53	56.7
1991	60	56.7
1992	62	56.7
1993	34	56.7
1994	75	56.7
1995	42	56.7
1996	65	56.7
1997	53	56.7
1998	58	56.7
1999	65	56.7
2000	69	74.3
2001	79	74.3
2002	75	74.3

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

First to last qualifying date each year at Alturas
Year	First date	Last date
1906	1906-06-20	1906-09-29
1907	1907-05-31	1907-09-24
1908	1908-06-13	1908-09-30
1909	1909-05-31	1909-09-23
1910	1910-04-24	1910-09-09
1911	1911-06-10	1911-09-01
1912	1912-06-01	1912-09-26
1913	1913-05-26	1913-09-20
1914	1914-05-29	1914-10-14
1915	1915-06-05	1915-10-07
1916	1916-06-07	1916-09-29
1917	1917-06-08	1917-10-10
1918	1918-06-04	1918-09-20
1919	1919-05-20	1919-09-25
1932	1932-06-21	1932-09-16
1933	1933-05-29	1933-10-07
1935	1935-06-04	1935-09-24
1936	1936-05-24	1936-10-11
1938	1938-06-05	1938-09-17
1939	1939-06-22	1939-09-23
1940	1940-06-11	1940-09-01
1943	1943-07-05	1943-09-24
1944	1944-06-30	1944-09-12
1945	1945-05-02	1945-09-14
1946	1946-06-20	1946-09-30
1947	1947-05-02	1947-10-06
1948	1948-06-29	1948-09-14
1949	1949-06-07	1949-09-24
1950	1950-05-31	1950-10-12
1951	1951-05-27	1951-09-20
1952	1952-06-05	1952-10-04
1954	1954-05-17	1954-09-27
1955	1955-06-07	1955-10-03
1956	1956-05-22	1956-10-07
1957	1957-06-19	1957-09-25
1958	1958-05-10	1958-10-06
1959	1959-05-13	1959-10-15
1960	1960-06-02	1960-10-01
1961	1961-06-14	1961-10-16
1962	1962-06-19	1962-10-02
1963	1963-05-18	1963-10-03
1964	1964-06-24	1964-10-07
1965	1965-06-05	1965-10-09
1966	1966-05-04	1966-10-06
1967	1967-05-17	1967-09-29
1968	1968-06-16	1968-10-04
1969	1969-05-08	1969-09-13
1970	1970-06-02	1970-10-05
1971	1971-07-14	1971-10-10
1972	1972-05-28	1972-09-18
1973	1973-05-18	1973-09-13
1975	1975-06-01	1975-09-08
1976	1976-05-14	1976-09-11
1977	1977-06-01	1977-09-11
1978	1978-06-05	1978-09-26
1979	1979-06-04	1979-10-06
1980	1980-06-29	1980-10-08
1981	1981-06-06	1981-09-19
1982	1982-05-26	1982-09-09
1983	1983-05-25	1983-09-17
1984	1984-05-29	1984-09-19
1985	1985-06-12	1985-09-05
1986	1986-05-26	1986-09-08
1987	1987-05-07	1987-10-07
1988	1988-05-12	1988-10-02
1989	1989-06-13	1989-09-25
1990	1990-05-06	1990-10-01
1991	1991-06-10	1991-10-16
1992	1992-05-06	1992-10-12
1993	1993-06-19	1993-10-04
1994	1994-05-25	1994-09-28
1995	1995-06-24	1995-09-19
1996	1996-06-02	1996-10-10
1997	1997-05-10	1997-09-24
1998	1998-07-05	1998-09-17
1999	1999-05-23	1999-09-23
2000	2000-05-21	2000-09-20
2001	2001-05-11	2001-10-03
2002	2002-05-29	2002-09-24

Every Fixed Threshold

Fixed thresholds at Alturas
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	79	92	1917	75
35 C (95 F): Days	75	33	1988	21
40 C (104 F): Days	13	4	1955	3
90 F (32.2 C): Days	79	73	1917	53
100 F (37.8 C): Days	47	13	1967	4
0 C (32 F): Ice days (max	76	44	1932	4
0 C (32 F): Frost days (min	80	233	1908	212
-10 C (14 F): Days with min	80	67	1917	24
-20 C (-4 F): Days with min	64	31	1917	1
-30 C (-22 F): Days with min	13	9	1917	1
10 mm (0.39 in): Days with 10 mm or more rain	90	17	1969	4
25 mm (0.98 in): Days with 25 mm or more rain	40	4	1986	1
50 mm (1.97 in): Days with 50 mm or more rain	5	1	1913	1
10 cm (3.9 in): Days with 10 cm or more snowfall	53	7	1970	3
25 cm (9.8 in): Days with 25 cm or more snowfall	8	2	1938	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1906.

Download the Data

Data for Alturas 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).

Alturas Threshold Days by Year (USC00040161)

Key Facts for Alturas Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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