Dillon Threshold Days by Year (USC00382386)

15 fixed thresholds counted per year at Dillon (USC00382386): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Dillon Thresholds

Dillon: days with 10 mm (0.39 in) or more of precipitation in 75 years, most in 1948 with 53.
Dillon: days with 25 mm (0.98 in) or more of precipitation in 75 years, most in 1908 with 21.
Dillon: days with 50 mm (1.97 in) or more of precipitation in 72 years, most in 1913 with 6.
Dillon: days with a maximum temperature at or above 30 C (86 F) in 68 years, most in 1941 with 149.
15 fixed thresholds have at least one qualifying day at Dillon.

Days at or above 30 C (86 F)

68 years with a qualifying day

Days per year at Dillon with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 149 in 1941.

Days at or above 30 C (86 F) per year at Dillon
Year	Days	Decade average
1905	126	118.5
1906	119	118.5
1907	120	118.5
1908	109	118.5
1910	126	114.6
1911	136	114.6
1913	103	114.6
1914	105	114.6
1915	103	114.6
1941	149	113.9
1942	137	113.9
1943	119	113.9
1944	112	113.9
1945	120	113.9
1946	88	113.9
1947	105	113.9
1948	99	113.9
1949	96	113.9
1950	100	109.5
1956	110	109.5
1957	113	109.5
1959	115	109.5
1960	117	98.3
1961	100	98.3
1962	115	98.3
1963	100	98.3
1964	89	98.3
1965	102	98.3
1966	79	98.3
1967	72	98.3
1968	119	98.3
1969	90	98.3
1970	128	109.1
1971	102	109.1
1972	92	109.1
1973	124	109.1
1974	110	109.1
1975	112	109.1
1976	101	109.1
1977	121	109.1
1978	114	109.1
1979	87	109.1
1980	122	108.9
1981	104	108.9
1982	118	108.9
1983	111	108.9
1984	119	108.9
1985	113	108.9
1987	106	108.9
1988	87	108.9
1989	100	108.9
1990	105	85.8
1991	101	85.8
1992	72	85.8
1993	101	85.8
1994	66	85.8
1995	77	85.8
1996	81	85.8
1997	82	85.8
1999	87	85.8
2000	78	93.8
2001	98	93.8
2002	117	93.8
2003	72	93.8
2004	75	93.8
2007	114	93.8
2008	99	93.8
2009	97	93.8

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

First to last qualifying date each year at Dillon
Year	First date	Last date
1905	1905-03-28	1905-10-20
1906	1906-04-22	1906-10-06
1907	1907-03-20	1907-10-08
1908	1908-03-08	1908-11-10
1910	1910-03-24	1910-10-21
1911	1911-04-03	1911-10-16
1913	1913-04-03	1913-10-24
1914	1914-04-24	1914-10-11
1915	1915-04-20	1915-10-26
1941	1941-04-14	1941-10-27
1942	1942-04-05	1942-10-05
1943	1943-04-27	1943-10-21
1944	1944-04-11	1944-10-08
1945	1945-03-16	1945-10-02
1946	1946-04-03	1946-10-12
1947	1947-04-06	1947-10-19
1948	1948-03-20	1948-09-21
1949	1949-05-04	1949-10-12
1950	1950-04-23	1950-10-04
1956	1956-05-13	1956-10-03
1957	1957-04-23	1957-09-24
1959	1959-04-09	1959-10-12
1960	1960-04-14	1960-10-07
1961	1961-04-25	1961-11-05
1962	1962-04-24	1962-10-15
1963	1963-03-19	1963-10-13
1964	1964-04-20	1964-10-01
1965	1965-04-10	1965-09-24
1966	1966-04-02	1966-09-28
1967	1967-03-16	1967-10-07
1968	1968-03-22	1968-10-04
1969	1969-04-06	1969-10-21
1970	1970-04-20	1970-10-15
1971	1971-04-14	1971-09-22
1972	1972-04-14	1972-10-18
1973	1973-05-11	1973-10-15
1974	1974-03-08	1974-11-04
1975	1975-04-29	1975-10-17
1976	1976-03-04	1976-10-09
1977	1977-04-12	1977-10-03
1978	1978-04-03	1978-10-06
1979	1979-05-05	1979-10-22
1980	1980-04-24	1980-10-12
1981	1981-04-13	1981-10-07
1982	1982-03-22	1982-10-06
1983	1983-04-29	1983-10-14
1984	1984-04-27	1984-10-31
1985	1985-03-30	1985-11-28
1987	1987-04-23	1987-09-19
1988	1988-05-17	1988-09-25
1989	1989-04-27	1989-09-23
1990	1990-04-26	1990-10-10
1991	1991-04-30	1991-09-20
1992	1992-04-25	1992-09-28
1993	1993-05-17	1993-10-10
1994	1994-05-13	1994-09-27
1995	1995-03-24	1995-10-09
1996	1996-05-05	1996-10-17
1997	1997-05-19	1997-10-09
1999	1999-04-05	1999-09-10
2000	2000-05-07	2000-10-07
2001	2001-04-08	2001-10-25
2002	2002-04-17	2002-10-06
2003	2003-05-03	2003-09-05
2004	2004-04-24	2004-09-17
2007	2007-03-25	2007-10-24
2008	2008-05-11	2008-10-16
2009	2009-04-25	2009-10-11

Every Fixed Threshold

Fixed thresholds at Dillon
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	68	149	1941	97
35 C (95 F): Days	67	48	1983	7
40 C (104 F): Days	5	4	1983	3
90 F (32.2 C): Days	68	109	1941	52
100 F (37.8 C): Days	32	17	1983	3
0 C (32 F): Ice days (max	35	5	1970	1
0 C (32 F): Frost days (min	66	107	1968	64
-10 C (14 F): Days with min	35	10	1970	3
20 C (68 F): Tropical nights (min	66	94	1995	49
25 C (77 F): Days with min	22	8	1983	1
10 mm (0.39 in): Days with 10 mm or more rain	75	53	1948	35
25 mm (0.98 in): Days with 25 mm or more rain	75	21	1908	15
50 mm (1.97 in): Days with 50 mm or more rain	72	6	1913	5
100 mm (3.94 in): Days with 100 mm or more rain	15	2	1945	1
10 cm (3.9 in): Days with 10 cm or more snowfall	5	1	1979	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1905.

Download the Data

Data for Dillon 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).

Dillon Threshold Days by Year (USC00382386)

Key Facts for Dillon Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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