Merriman Threshold Days by Year (USC00255470)

20 fixed thresholds counted per year at Merriman (USC00255470): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Merriman Thresholds

Merriman: days with a maximum temperature at or above 30 C (86 F) in 79 years, most in 1931 with 92.
Merriman: days with a maximum temperature at or above 35 C (95 F) in 79 years, most in 1936 with 51.
Merriman: days with a maximum temperature at or above 90 F (32.2 C) in 79 years, most in 1936 with 71.
Merriman: days with a maximum temperature at or below 0 C (32 F) in 79 years, most in 1978 with 72.
20 fixed thresholds have at least one qualifying day at Merriman.

Days at or above 30 C (86 F)

79 years with a qualifying day

Days per year at Merriman with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 92 in 1931.

Days at or above 30 C (86 F) per year at Merriman
Year	Days	Decade average
1918	63	66
1919	69	66
1920	53	57.8
1921	57	57.8
1922	64	57.8
1923	46	57.8
1924	45	57.8
1925	53	57.8
1926	55	57.8
1927	71	57.8
1928	76	57.8
1930	71	77.5
1931	92	77.5
1932	69	77.5
1934	70	77.5
1935	70	77.5
1936	89	77.5
1938	76	77.5
1939	83	77.5
1940	83	65.7
1941	65	65.7
1942	52	65.7
1943	72	65.7
1944	53	65.7
1945	54	65.7
1946	72	65.7
1947	77	65.7
1949	63	65.7
1950	45	64.4
1951	32	64.4
1952	73	64.4
1953	64	64.4
1954	71	64.4
1955	78	64.4
1956	76	64.4
1957	59	64.4
1958	68	64.4
1959	78	64.4
1960	65	59.9
1961	72	59.9
1962	47	59.9
1963	85	59.9
1964	59	59.9
1965	46	59.9
1966	57	59.9
1968	48	59.9
1970	78	58.4
1971	51	58.4
1972	43	58.4
1973	52	58.4
1974	59	58.4
1975	62	58.4
1976	68	58.4
1977	47	58.4
1978	66	58.4
1980	73	65.9
1981	55	65.9
1982	53	65.9
1983	72	65.9
1984	76	65.9
1985	60	65.9
1986	50	65.9
1987	75	65.9
1988	87	65.9
1989	58	65.9
1990	53	52.4
1991	58	52.4
1992	36	52.4
1993	29	52.4
1994	61	52.4
1995	58	52.4
1996	57	52.4
1997	57	52.4
1998	62	52.4
1999	53	52.4
2000	78	64.3
2002	72	64.3
2004	52	64.3
2005	55	64.3

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

First to last qualifying date each year at Merriman
Year	First date	Last date
1918	1918-05-03	1918-10-14
1919	1919-06-12	1919-09-30
1920	1920-06-07	1920-10-09
1921	1921-06-10	1921-09-28
1922	1922-06-05	1922-10-28
1923	1923-06-02	1923-09-23
1924	1924-05-04	1924-09-24
1925	1925-05-19	1925-09-16
1926	1926-04-29	1926-10-07
1927	1927-04-27	1927-10-26
1928	1928-03-21	1928-10-10
1930	1930-04-06	1930-10-10
1931	1931-05-15	1931-11-08
1932	1932-05-13	1932-09-30
1934	1934-04-30	1934-09-12
1935	1935-06-08	1935-09-24
1936	1936-05-05	1936-09-22
1938	1938-04-30	1938-10-03
1939	1939-05-01	1939-09-23
1940	1940-05-11	1940-09-27
1941	1941-05-12	1941-09-20
1942	1942-04-14	1942-10-11
1943	1943-05-27	1943-09-18
1944	1944-05-13	1944-09-14
1945	1945-06-21	1945-09-21
1946	1946-03-31	1946-10-01
1947	1947-06-16	1947-10-21
1949	1949-04-24	1949-09-25
1950	1950-05-17	1950-10-30
1951	1951-07-06	1951-10-01
1952	1952-04-26	1952-09-29
1953	1953-05-28	1953-10-11
1954	1954-05-20	1954-10-08
1955	1955-04-26	1955-10-10
1956	1956-05-08	1956-10-12
1957	1957-05-07	1957-10-01
1958	1958-04-16	1958-10-19
1959	1959-05-01	1959-09-14
1960	1960-05-13	1960-10-09
1961	1961-04-19	1961-10-16
1962	1962-04-20	1962-10-14
1963	1963-05-07	1963-10-18
1964	1964-04-16	1964-10-15
1965	1965-04-30	1965-10-09
1966	1966-05-04	1966-09-23
1968	1968-04-30	1968-10-30
1970	1970-05-07	1970-10-05
1971	1971-06-16	1971-09-14
1972	1972-05-16	1972-09-19
1973	1973-05-18	1973-09-01
1974	1974-05-19	1974-09-26
1975	1975-06-03	1975-10-07
1976	1976-06-02	1976-10-02
1977	1977-06-02	1977-09-21
1978	1978-05-14	1978-09-26
1980	1980-04-21	1980-10-13
1981	1981-04-25	1981-09-29
1982	1982-05-03	1982-09-11
1983	1983-05-27	1983-10-01
1984	1984-05-16	1984-09-22
1985	1985-04-12	1985-09-19
1986	1986-06-03	1986-09-10
1987	1987-04-18	1987-10-04
1988	1988-04-08	1988-10-15
1989	1989-04-21	1989-10-01
1990	1990-04-23	1990-10-06
1991	1991-04-07	1991-10-17
1992	1992-05-01	1992-10-22
1993	1993-05-27	1993-10-07
1994	1994-04-24	1994-09-29
1995	1995-06-14	1995-10-13
1996	1996-04-11	1996-10-14
1997	1997-05-11	1997-10-05
1998	1998-05-18	1998-09-29
1999	1999-05-30	1999-10-07
2000	2000-05-05	2000-09-29
2002	2002-05-30	2002-09-17
2004	2004-05-06	2004-09-19
2005	2005-06-07	2005-10-03

Every Fixed Threshold

Fixed thresholds at Merriman
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	79	92	1931	55
35 C (95 F): Days	79	51	1936	17
40 C (104 F): Days	44	17	1936	1
90 F (32.2 C): Days	79	71	1936	34
100 F (37.8 C): Days	72	33	1936	7
110 F (43.3 C): Days	4	1	1936	1
0 C (32 F): Ice days (max	79	72	1978	37
0 C (32 F): Frost days (min	76	196	1927	159
-10 C (14 F): Days with min	76	97	1978	42
-20 C (-4 F): Days with min	76	32	1924	11
-30 C (-22 F): Days with min	36	8	1989	2
-40 C (-40 F): Days with min	1	1	1983	1
20 C (68 F): Tropical nights (min	68	16	2002	9
10 mm (0.39 in): Days with 10 mm or more rain	79	26	1951	15
25 mm (0.98 in): Days with 25 mm or more rain	75	8	1998	5
50 mm (1.97 in): Days with 50 mm or more rain	27	2	1898	1
100 mm (3.94 in): Days with 100 mm or more rain	2	1	1919	1
10 cm (3.9 in): Days with 10 cm or more snowfall	53	7	1993	1
25 cm (9.8 in): Days with 25 cm or more snowfall	5	2	1977	1
50 cm (19.7 in): Days with 50 cm or more snowfall	1	1	1920	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1918.

Download the Data

Data for Merriman 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).

Merriman Threshold Days by Year (USC00255470)

Key Facts for Merriman Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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