Diversion Dam Threshold Days by Year (USC00482595)

16 fixed thresholds counted per year at Diversion Dam (USC00482595): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Diversion Dam Thresholds

Diversion Dam: nights with a minimum temperature at or below 0 C (32 F) in 74 years, most in 2002 with 218.
Diversion Dam: nights with a minimum temperature at or below -10 C (14 F) in 74 years, most in 2023 with 111.
Diversion Dam: nights with a minimum temperature at or below -20 C (-4 F) in 72 years, most in 1932 with 46.
Diversion Dam: days with a maximum temperature at or above 30 C (86 F) in 70 years, most in 1922 with 62.
16 fixed thresholds have at least one qualifying day at Diversion Dam.

Days at or above 30 C (86 F)

70 years with a qualifying day

Days per year at Diversion Dam with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 62 in 1922.

Days at or above 30 C (86 F) per year at Diversion Dam
Year	Days	Decade average
1921	49	39.2
1922	62	39.2
1923	31	39.2
1924	34	39.2
1925	31	39.2
1926	50	39.2
1927	23	39.2
1928	25	39.2
1929	48	39.2
1930	23	43.6
1931	51	43.6
1932	51	43.6
1933	53	43.6
1934	40	43.6
1935	49	43.6
1937	54	43.6
1938	28	43.6
1939	43	43.6
1940	56	44.5
1949	33	44.5
1950	20	38.4
1951	22	38.4
1952	42	38.4
1953	51	38.4
1954	48	38.4
1955	51	38.4
1956	40	38.4
1957	32	38.4
1958	29	38.4
1959	49	38.4
1960	45	36.3
1961	42	36.3
1962	33	36.3
1963	25	36.3
1964	45	36.3
1965	21	36.3
1966	50	36.3
1967	32	36.3
1968	34	36.3
1970	52	38.6
1971	46	38.6
1972	27	38.6
1973	33	38.6
1974	50	38.6
1975	28	38.6
1976	37	38.6
1977	37	38.6
1978	37	38.6
1979	39	38.6
1980	40	39.2
1981	46	39.2
1982	27	39.2
1983	39	39.2
1984	44	39.2
1994	32	25
1995	19	25
1996	24	25
1997	17	25
1998	29	25
1999	29	25
2002	32	37.7
2007	44	37.7
2008	37	37.7
2010	33	43.5
2011	35	43.5
2015	38	43.5
2017	53	43.5
2018	49	43.5
2019	53	43.5
2023	27	27

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

First to last qualifying date each year at Diversion Dam
Year	First date	Last date
1921	1921-06-11	1921-09-01
1922	1922-06-12	1922-09-21
1923	1923-06-29	1923-09-04
1924	1924-06-14	1924-09-05
1925	1925-05-28	1925-08-31
1926	1926-05-23	1926-09-16
1927	1927-05-16	1927-09-03
1928	1928-07-04	1928-09-07
1929	1929-06-25	1929-08-31
1930	1930-06-11	1930-08-20
1931	1931-06-15	1931-09-09
1932	1932-06-22	1932-09-09
1933	1933-06-10	1933-09-07
1934	1934-05-27	1934-09-04
1935	1935-06-22	1935-09-11
1937	1937-06-20	1937-09-19
1938	1938-06-17	1938-08-23
1939	1939-05-29	1939-09-01
1940	1940-05-31	1940-09-08
1949	1949-07-01	1949-08-26
1950	1950-06-30	1950-09-06
1951	1951-07-04	1951-08-18
1952	1952-06-06	1952-09-10
1953	1953-06-11	1953-09-13
1954	1954-05-19	1954-09-11
1955	1955-06-20	1955-09-13
1956	1956-06-09	1956-09-21
1957	1957-06-04	1957-08-24
1958	1958-06-15	1958-09-08
1959	1959-06-06	1959-09-13
1960	1960-05-12	1960-09-04
1961	1961-06-09	1961-08-27
1962	1962-06-26	1962-09-06
1963	1963-07-15	1963-09-30
1964	1964-06-26	1964-09-06
1965	1965-07-08	1965-08-14
1966	1966-05-06	1966-09-08
1967	1967-06-30	1967-09-02
1968	1968-06-03	1968-08-08
1970	1970-06-22	1970-08-26
1971	1971-06-20	1971-09-13
1972	1972-06-28	1972-08-15
1973	1973-06-08	1973-08-30
1974	1974-06-12	1974-09-09
1975	1975-07-01	1975-09-08
1976	1976-06-20	1976-09-06
1977	1977-06-01	1977-09-08
1978	1978-06-19	1978-09-11
1979	1979-06-11	1979-09-17
1980	1980-05-23	1980-09-30
1981	1981-06-22	1981-09-12
1982	1982-06-27	1982-09-09
1983	1983-07-05	1983-09-08
1984	1984-05-30	1984-09-18
1994	1994-06-19	1994-08-27
1995	1995-07-10	1995-09-03
1996	1996-06-09	1996-09-01
1997	1997-06-23	1997-08-29
1998	1998-07-06	1998-09-08
1999	1999-07-04	1999-08-31
2002	2002-05-31	2002-09-05
2007	2007-06-16	2007-09-04
2008	2008-06-30	2008-08-31
2010	2010-06-29	2010-09-29
2011	2011-06-28	2011-08-31
2015	2015-06-19	2015-09-26
2017	2017-06-05	2017-09-12
2018	2018-06-04	2018-09-16
2019	2019-06-26	2019-09-15
2023	2023-07-02	2023-08-31

Every Fixed Threshold

Fixed thresholds at Diversion Dam
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	70	62	1922	27
35 C (95 F): Days	46	12	1940	1
90 F (32.2 C): Days	70	39	1940	13
100 F (37.8 C): Days	5	2	1931	1
0 C (32 F): Ice days (max	70	87	2023	87
0 C (32 F): Frost days (min	74	218	2002	184
-10 C (14 F): Days with min	74	111	2023	111
-20 C (-4 F): Days with min	72	46	1932	29
-30 C (-22 F): Days with min	46	12	1949	5
-40 C (-40 F): Days with min	3	3	1924	1
20 C (68 F): Tropical nights (min	5	1	1977	1
10 mm (0.39 in): Days with 10 mm or more rain	70	22	2023	22
25 mm (0.98 in): Days with 25 mm or more rain	40	6	2023	6
50 mm (1.97 in): Days with 50 mm or more rain	9	1	1950	1
10 cm (3.9 in): Days with 10 cm or more snowfall	36	4	1938	4
25 cm (9.8 in): Days with 25 cm or more snowfall	4	1	1932	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1921.

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Data for Diversion Dam 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).

Diversion Dam Threshold Days by Year (USC00482595)

Key Facts for Diversion Dam Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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