Mtn Dell Dam Threshold Days by Year (USC00425892)

17 fixed thresholds counted per year at Mtn Dell Dam (USC00425892): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Mtn Dell Dam Thresholds

Mtn Dell Dam: days with 10 mm (0.39 in) or more of precipitation in 91 years, most in 1983 with 36.
Mtn Dell Dam: days with 25 mm (0.98 in) or more of precipitation in 82 years, most in 1982 with 6.
Mtn Dell Dam: nights with a minimum temperature at or below 0 C (32 F) in 77 years, most in 1966 with 212.
Mtn Dell Dam: nights with a minimum temperature at or below -10 C (14 F) in 77 years, most in 1966 with 77.
17 fixed thresholds have at least one qualifying day at Mtn Dell Dam.

Days at or above 30 C (86 F)

75 years with a qualifying day

Days per year at Mtn Dell Dam with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 83 in 1988.

Days at or above 30 C (86 F) per year at Mtn Dell Dam
Year	Days	Decade average
1941	21	38.6
1942	35	38.6
1943	48	38.6
1944	42	38.6
1945	28	38.6
1946	68	38.6
1947	30	38.6
1948	46	38.6
1949	29	38.6
1950	30	46.6
1951	27	46.6
1952	31	46.6
1953	46	46.6
1954	45	46.6
1955	48	46.6
1956	57	46.6
1957	49	46.6
1958	67	46.6
1959	66	46.6
1960	80	61.4
1961	77	61.4
1962	74	61.4
1963	74	61.4
1965	32	61.4
1966	77	61.4
1967	52	61.4
1968	34	61.4
1969	53	61.4
1970	58	51.9
1971	47	51.9
1972	38	51.9
1973	50	51.9
1974	68	51.9
1975	40	51.9
1976	50	51.9
1977	61	51.9
1978	55	51.9
1980	51	52.8
1981	63	52.8
1982	42	52.8
1983	41	52.8
1984	34	52.8
1985	63	52.8
1986	52	52.8
1987	44	52.8
1988	83	52.8
1989	55	52.8
1996	80	51.3
1997	49	51.3
1998	40	51.3
1999	36	51.3
2000	57	55.1
2001	66	55.1
2003	66	55.1
2004	42	55.1
2005	48	55.1
2006	54	55.1
2008	55	55.1
2009	53	55.1
2010	50	62.1
2011	47	62.1
2012	69	62.1
2013	62	62.1
2014	48	62.1
2015	66	62.1
2016	70	62.1
2017	70	62.1
2018	77	62.1
2020	77	70.6
2021	70	70.6
2022	79	70.6
2023	46	70.6
2024	73	70.6
2025	77	70.6
2026	72	70.6

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

First to last qualifying date each year at Mtn Dell Dam
Year	First date	Last date
1941	1941-06-21	1941-08-05
1942	1942-07-04	1942-09-02
1943	1943-06-26	1943-09-17
1944	1944-07-18	1944-09-13
1945	1945-06-22	1945-09-05
1946	1946-06-03	1946-09-13
1947	1947-05-03	1947-09-23
1948	1948-05-16	1948-09-15
1949	1949-07-01	1949-08-21
1950	1950-06-21	1950-09-05
1951	1951-07-01	1951-09-17
1952	1952-06-09	1952-09-09
1953	1953-06-11	1953-09-15
1954	1954-05-19	1954-09-22
1955	1955-06-21	1955-09-13
1956	1956-05-31	1956-09-19
1957	1957-06-04	1957-09-30
1958	1958-05-19	1958-09-11
1959	1959-06-05	1959-09-13
1960	1960-05-11	1960-09-28
1961	1961-05-24	1961-09-06
1962	1962-06-10	1962-09-21
1963	1963-06-27	1963-10-03
1965	1965-06-21	1965-08-28
1966	1966-05-06	1966-09-23
1967	1967-05-22	1967-09-05
1968	1968-06-17	1968-09-11
1969	1969-05-27	1969-09-08
1970	1970-05-17	1970-09-02
1971	1971-06-18	1971-09-12
1972	1972-06-01	1972-08-22
1973	1973-06-09	1973-09-06
1974	1974-06-12	1974-09-10
1975	1975-06-30	1975-09-01
1976	1976-06-20	1976-09-06
1977	1977-06-01	1977-09-08
1978	1978-06-13	1978-09-07
1980	1980-06-18	1980-09-06
1981	1981-06-22	1981-09-05
1982	1982-06-27	1982-09-04
1983	1983-06-22	1983-09-01
1984	1984-05-29	1984-09-05
1985	1985-06-07	1985-09-02
1986	1986-06-14	1986-09-05
1987	1987-06-04	1987-09-10
1988	1988-06-03	1988-09-10
1989	1989-06-15	1989-09-06
1996	1996-05-13	1996-10-11
1997	1997-05-31	1997-08-30
1998	1998-06-30	1998-09-05
1999	1999-06-18	1999-08-30
2000	2000-06-05	2000-09-17
2001	2001-06-02	2001-09-25
2003	2003-05-23	2003-08-28
2004	2004-06-03	2004-09-11
2005	2005-06-20	2005-09-03
2006	2006-06-06	2006-09-05
2008	2008-05-20	2008-08-31
2009	2009-05-18	2009-09-05
2010	2010-06-24	2010-09-20
2011	2011-06-23	2011-09-02
2012	2012-06-03	2012-09-10
2013	2013-06-09	2013-09-07
2014	2014-05-28	2014-09-19
2015	2015-05-31	2015-09-26
2016	2016-06-05	2016-09-20
2017	2017-05-31	2017-09-12
2018	2018-06-04	2018-09-16
2020	2020-05-29	2020-09-18
2021	2021-06-03	2021-09-11
2022	2022-06-10	2022-09-13
2023	2023-07-02	2023-09-01
2024	2024-06-06	2024-10-05
2025	2025-06-01	2025-09-11
2026	2026-05-11	2026-09-14

Every Fixed Threshold

Fixed thresholds at Mtn Dell Dam
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	75	83	1988	72
35 C (95 F): Days	56	29	1960	23
90 F (32.2 C): Days	75	63	1961	53
100 F (37.8 C): Days	5	7	1960	3
0 C (32 F): Ice days (max	75	51	1949	3
0 C (32 F): Frost days (min	77	212	1966	101
-10 C (14 F): Days with min	77	77	1966	20
-20 C (-4 F): Days with min	58	20	1949	2
-30 C (-22 F): Days with min	1	3	1963	3
20 C (68 F): Tropical nights (min	15	3	2015	1
10 mm (0.39 in): Days with 10 mm or more rain	91	36	1983	18
25 mm (0.98 in): Days with 25 mm or more rain	82	6	1982	2
50 mm (1.97 in): Days with 50 mm or more rain	12	1	1926	1
100 mm (3.94 in): Days with 100 mm or more rain	1	1	2004	1
10 cm (3.9 in): Days with 10 cm or more snowfall	70	22	1952	1
25 cm (9.8 in): Days with 25 cm or more snowfall	53	5	1955	3
50 cm (19.7 in): Days with 50 cm or more snowfall	3	1	1974	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1941.

Download the Data

Data for Mtn Dell 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 2026-10-17. Last revised 17 October 2026 (2026-10-17).

Mtn Dell Dam Threshold Days by Year (USC00425892)

Key Facts for Mtn Dell Dam Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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