Rochester Threshold Days by Year (USC00127482)

18 fixed thresholds counted per year at Rochester (USC00127482): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Rochester Thresholds

Rochester: nights with a minimum temperature at or below 0 C (32 F) in 106 years, most in 1925 with 166.
Rochester: nights with a minimum temperature at or below -10 C (14 F) in 106 years, most in 1978 with 65.
Rochester: nights with a minimum temperature at or above 20 C (68 F) in 106 years, most in 1949 with 38.
Rochester: days with 10 mm (0.39 in) or more of precipitation in 106 years, most in 1990 with 52.
18 fixed thresholds have at least one qualifying day at Rochester.

Days at or above 30 C (86 F)

105 years with a qualifying day

Days per year at Rochester with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 84 in 1939.

Days at or above 30 C (86 F) per year at Rochester
Year	Days	Decade average
1905	43	31.3
1907	12	31.3
1908	43	31.3
1909	27	31.3
1910	42	38.3
1911	49	38.3
1912	33	38.3
1915	29	38.3
1925	73	60
1929	47	60
1930	61	66.3
1931	64	66.3
1932	56	66.3
1933	71	66.3
1934	79	66.3
1935	57	66.3
1936	77	66.3
1937	54	66.3
1938	60	66.3
1939	84	66.3
1940	60	56.6
1941	79	56.6
1942	50	56.6
1943	57	56.6
1944	70	56.6
1945	36	56.6
1946	58	56.6
1947	53	56.6
1948	46	56.6
1949	57	56.6
1950	25	45.5
1951	23	45.5
1952	50	45.5
1953	62	45.5
1954	54	45.5
1955	67	45.5
1956	49	45.5
1957	42	45.5
1958	21	45.5
1959	62	45.5
1960	28	39.9
1961	43	39.9
1962	44	39.9
1963	39	39.9
1964	51	39.9
1965	32	39.9
1966	53	39.9
1967	31	39.9
1968	40	39.9
1969	38	39.9
1970	46	40.5
1971	43	40.5
1972	32	40.5
1973	40	40.5
1974	34	40.5
1975	47	40.5
1976	35	40.5
1977	49	40.5
1978	47	40.5
1979	32	40.5
1980	54	38.8
1981	21	38.8
1982	40	38.8
1983	76	38.8
1984	30	38.8
1985	18	38.8
1986	27	38.8
1987	48	38.8
1988	54	38.8
1989	20	38.8
1990	18	28.5
1991	49	28.5
1992	9	28.5
1993	23	28.5
1994	26	28.5
1995	45	28.5
1996	23	28.5
1997	18	28.5
1998	34	28.5
1999	40	28.5
2000	19	32
2001	29	32
2002	51	32
2003	22	32
2004	23	32
2005	56	32
2006	25	32
2007	51	32
2008	25	32
2009	19	32
2010	58	44
2011	50	44
2012	58	44
2015	23	44
2016	47	44
2017	30	44
2018	49	44
2019	37	44
2020	43	40.3
2021	49	40.3
2022	38	40.3
2023	30	40.3
2024	37	40.3
2025	49	40.3
2026	36	40.3

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

First to last qualifying date each year at Rochester
Year	First date	Last date
1905	1905-06-04	1905-10-09
1907	1907-06-16	1907-08-11
1908	1908-05-25	1908-09-24
1909	1909-06-07	1909-08-27
1910	1910-06-15	1910-08-17
1911	1911-05-16	1911-09-02
1912	1912-06-04	1912-09-14
1915	1915-04-24	1915-09-15
1925	1925-04-24	1925-09-20
1929	1929-05-30	1929-09-29
1930	1930-04-10	1930-10-12
1931	1931-05-18	1931-10-05
1932	1932-05-15	1932-09-19
1933	1933-05-23	1933-09-25
1934	1934-05-04	1934-09-26
1935	1935-06-13	1935-09-25
1936	1936-05-07	1936-09-22
1937	1937-05-30	1937-10-01
1938	1938-05-03	1938-10-18
1939	1939-05-17	1939-10-09
1940	1940-06-03	1940-10-05
1941	1941-04-13	1941-09-24
1942	1942-04-30	1942-09-18
1943	1943-06-02	1943-09-03
1944	1944-05-15	1944-09-27
1945	1945-06-14	1945-09-23
1946	1946-06-07	1946-10-07
1947	1947-06-09	1947-09-20
1948	1948-06-03	1948-09-20
1949	1949-05-04	1949-10-09
1950	1950-05-24	1950-10-17
1951	1951-05-01	1951-10-04
1952	1952-05-05	1952-09-14
1953	1953-05-26	1953-10-21
1954	1954-05-25	1954-09-28
1955	1955-05-04	1955-09-20
1956	1956-05-13	1956-09-23
1957	1957-04-28	1957-09-02
1958	1958-07-01	1958-09-07
1959	1959-05-03	1959-09-29
1960	1960-06-05	1960-09-09
1961	1961-06-06	1961-09-23
1962	1962-05-01	1962-09-15
1963	1963-05-09	1963-10-08
1964	1964-05-19	1964-09-11
1965	1965-05-19	1965-09-21
1966	1966-05-28	1966-09-04
1967	1967-05-26	1967-10-05
1968	1968-06-07	1968-09-04
1969	1969-05-29	1969-09-02
1970	1970-05-21	1970-09-22
1971	1971-05-18	1971-10-03
1972	1972-05-24	1972-09-18
1973	1973-06-04	1973-09-27
1974	1974-05-22	1974-09-12
1975	1975-05-19	1975-09-04
1976	1976-06-08	1976-09-15
1977	1977-04-19	1977-09-03
1978	1978-05-27	1978-09-21
1979	1979-05-09	1979-09-01
1980	1980-04-23	1980-09-23
1981	1981-06-15	1981-09-14
1982	1982-05-13	1982-09-12
1983	1983-06-11	1983-09-20
1984	1984-05-19	1984-09-03
1985	1985-05-13	1985-09-09
1986	1986-04-26	1986-09-30
1987	1987-05-11	1987-09-07
1988	1988-05-16	1988-09-18
1989	1989-05-31	1989-08-28
1990	1990-06-14	1990-09-07
1991	1991-05-14	1991-09-16
1992	1992-06-18	1992-08-27
1993	1993-05-10	1993-08-31
1994	1994-05-23	1994-09-16
1995	1995-06-17	1995-09-07
1996	1996-05-19	1996-08-23
1997	1997-06-20	1997-08-17
1998	1998-05-16	1998-09-27
1999	1999-05-30	1999-09-27
2000	2000-05-09	2000-09-21
2001	2001-05-16	2001-09-09
2002	2002-06-01	2002-09-20
2003	2003-06-19	2003-08-29
2004	2004-04-19	2004-09-24
2005	2005-05-11	2005-10-05
2006	2006-05-28	2006-08-03
2007	2007-05-02	2007-10-09
2008	2008-06-06	2008-10-13
2009	2009-06-20	2009-08-26
2010	2010-05-24	2010-10-11
2011	2011-05-11	2011-09-05
2012	2012-03-22	2012-09-04
2015	2015-05-08	2015-09-18
2016	2016-05-25	2016-09-26
2017	2017-05-18	2017-09-27
2018	2018-05-15	2018-10-10
2019	2019-05-19	2019-10-02
2020	2020-05-25	2020-09-04
2021	2021-05-23	2021-09-28
2022	2022-05-12	2022-09-22
2023	2023-05-31	2023-10-05
2024	2024-05-20	2024-09-22
2025	2025-05-16	2025-10-05
2026	2026-06-07	2026-10-14

Every Fixed Threshold

Fixed thresholds at Rochester
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	105	84	1939	36
35 C (95 F): Days	69	30	1934	1
40 C (104 F): Days	3	7	1934	6
90 F (32.2 C): Days	103	57	1934	17
100 F (37.8 C): Days	24	12	1936	2
0 C (32 F): Ice days (max	105	69	1960	30
0 C (32 F): Frost days (min	106	166	1925	78
-10 C (14 F): Days with min	106	65	1978	21
-20 C (-4 F): Days with min	83	29	1963	3
-30 C (-22 F): Days with min	3	1	1982	1
20 C (68 F): Tropical nights (min	106	38	1949	26
25 C (77 F): Days with min	14	3	1936	1
10 mm (0.39 in): Days with 10 mm or more rain	106	52	1990	32
25 mm (0.98 in): Days with 25 mm or more rain	106	17	1990	9
50 mm (1.97 in): Days with 50 mm or more rain	82	5	1990	1
100 mm (3.94 in): Days with 100 mm or more rain	10	1	1932	1
10 cm (3.9 in): Days with 10 cm or more snowfall	70	9	2000	2
25 cm (9.8 in): Days with 25 cm or more snowfall	6	1	1987	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 Rochester 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).

Rochester Threshold Days by Year (USC00127482)

Key Facts for Rochester Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

Related