Pomona Post Office Threshold Days by Year

5 fixed thresholds counted per year at Pomona Post Office (ASN00040176): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Pomona Post Office Thresholds

Pomona Post Office: days with 10 mm (0.39 in) or more of precipitation in 77 years, most in 1950 with 62.
Pomona Post Office: days with 25 mm (0.98 in) or more of precipitation in 77 years, most in 1927 with 30.
Pomona Post Office: days with 50 mm (1.97 in) or more of precipitation in 75 years, most in 1956 with 13.
Pomona Post Office: days with 100 mm (3.94 in) or more of precipitation in 51 years, most in 1968 with 4.
5 fixed thresholds have at least one qualifying day at Pomona Post Office.

Days with 10 mm (0.39 in) or more of precipitation

77 years with a qualifying day

Days per year at Pomona Post Office with 10 mm (0.39 in) or more of precipitation, with the decade average as a line. The most was 62 in 1950.

Days with 10 mm (0.39 in) or more of precipitation per year at Pomona Post Office
Year	Days	Decade average
1920	47	43.2
1921	53	43.2
1922	35	43.2
1923	37	43.2
1924	39	43.2
1925	48	43.2
1926	41	43.2
1927	57	43.2
1928	43	43.2
1929	32	43.2
1930	48	38.8
1931	46	38.8
1932	24	38.8
1933	39	38.8
1934	43	38.8
1935	46	38.8
1936	31	38.8
1937	30	38.8
1938	43	38.8
1939	38	38.8
1940	35	34.1
1941	27	34.1
1942	34	34.1
1943	40	34.1
1944	34	34.1
1945	35	34.1
1946	29	34.1
1947	41	34.1
1948	30	34.1
1949	36	34.1
1950	62	39.8
1951	16	39.8
1952	33	39.8
1953	39	39.8
1954	44	39.8
1955	43	39.8
1956	47	39.8
1957	19	39.8
1958	45	39.8
1959	50	39.8
1960	25	35.7
1961	41	35.7
1962	41	35.7
1963	36	35.7
1964	31	35.7
1965	41	35.7
1966	32	35.7
1967	40	35.7
1968	34	35.7
1970	35	42
1971	47	42
1972	41	42
1973	50	42
1974	54	42
1975	35	42
1976	54	42
1977	31	42
1978	42	42
1979	31	42
1980	37	38.1
1981	43	38.1
1983	44	38.1
1985	29	38.1
1986	32	38.1
1987	33	38.1
1988	43	38.1
1989	44	38.1
1990	36	32.2
1991	25	32.2
1992	36	32.2
1993	43	32.2
1994	33	32.2
1995	36	32.2
1996	30	32.2
1997	24	32.2
1998	27	32.2
2001	18	18

For each year, a bar from the first to the last day at Pomona Post Office meeting 10 mm (0.39 in).

First to last qualifying date each year at Pomona Post Office
Year	First date	Last date
1920	1920-01-02	1920-12-09
1921	1921-01-07	1921-12-31
1922	1922-01-09	1922-12-27
1923	1923-01-07	1923-12-24
1924	1924-01-25	1924-12-31
1925	1925-01-03	1925-12-31
1926	1926-01-02	1926-12-29
1927	1927-01-01	1927-12-26
1928	1928-01-09	1928-12-20
1929	1929-01-12	1929-12-31
1930	1930-01-01	1930-12-18
1931	1931-01-20	1931-12-30
1932	1932-02-08	1932-12-22
1933	1933-01-18	1933-12-29
1934	1934-01-02	1934-12-26
1935	1935-01-07	1935-12-28
1936	1936-01-10	1936-12-16
1937	1937-02-11	1937-12-16
1938	1938-01-08	1938-12-02
1939	1939-01-19	1939-12-27
1940	1940-01-05	1940-12-22
1941	1941-01-15	1941-12-30
1942	1942-01-17	1942-12-31
1943	1943-01-04	1943-12-31
1944	1944-01-02	1944-12-22
1945	1945-01-01	1945-12-24
1946	1946-01-14	1946-12-31
1947	1947-01-01	1947-12-22
1948	1948-01-03	1948-12-27
1949	1949-01-10	1949-12-17
1950	1950-01-05	1950-12-25
1951	1951-01-25	1951-12-16
1952	1952-01-09	1952-12-23
1953	1953-01-01	1953-12-28
1954	1954-01-04	1954-12-18
1955	1955-01-23	1955-12-31
1956	1956-01-06	1956-12-24
1957	1957-01-09	1957-12-14
1958	1958-01-21	1958-12-29
1959	1959-01-03	1959-12-28
1960	1960-01-02	1960-12-07
1961	1961-01-04	1961-12-19
1962	1962-01-05	1962-12-29
1963	1963-01-01	1963-12-18
1964	1964-01-01	1964-12-26
1965	1965-01-04	1965-12-21
1966	1966-01-19	1966-12-30
1967	1967-01-02	1967-12-20
1968	1968-01-08	1968-12-29
1970	1970-01-08	1970-12-25
1971	1971-01-14	1971-12-28
1972	1972-01-08	1972-12-29
1973	1973-01-08	1973-12-21
1974	1974-01-01	1974-12-28
1975	1975-01-06	1975-12-24
1976	1976-01-11	1976-12-25
1977	1977-01-05	1977-11-19
1978	1978-01-27	1978-12-31
1979	1979-01-20	1979-12-21
1980	1980-01-06	1980-12-30
1981	1981-01-01	1981-12-30
1983	1983-03-03	1983-12-31
1985	1985-01-01	1985-12-22
1986	1986-01-10	1986-12-27
1987	1987-01-05	1987-12-02
1988	1988-01-01	1988-12-28
1989	1989-01-06	1989-12-25
1990	1990-01-16	1990-12-22
1991	1991-01-03	1991-12-22
1992	1992-01-01	1992-12-27
1993	1993-01-06	1993-12-23
1994	1994-01-12	1994-12-10
1995	1995-01-09	1995-12-24
1996	1996-01-04	1996-12-19
1997	1997-01-25	1997-12-29
1998	1998-01-29	1998-12-19
2001	2001-02-01	2001-12-31

Every Fixed Threshold

Fixed thresholds at Pomona Post Office
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
10 mm (0.39 in): Days with 10 mm or more rain	77	62	1950	18
25 mm (0.98 in): Days with 25 mm or more rain	77	30	1927	5
50 mm (1.97 in): Days with 50 mm or more rain	75	13	1956	1
100 mm (3.94 in): Days with 100 mm or more rain	51	4	1968	1
200 mm (7.87 in): Days with 200 mm or more rain	13	2	1992	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1920.

Download the Data

Data for Pomona Post Office 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 2026-10-15 (15 October 2026). Threshold counts are computed by this site.

Data as of 2025-12-31. Last revised 31 December 2025 (2025-12-31).

Pomona Post Office Threshold Days by Year

Key Facts for Pomona Post Office Thresholds

Days with 10 mm (0.39 in) or more of precipitation

Every Fixed Threshold

Download the Data

Related