Charleston Threshold Days by Year (USC00221606)

17 fixed thresholds counted per year at Charleston (USC00221606): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Charleston Thresholds

Charleston: days with 10 mm (0.39 in) or more of precipitation in 55 years, most in 1974 with 62.
Charleston: days with 25 mm (0.98 in) or more of precipitation in 55 years, most in 1957 with 28.
Charleston: days with 50 mm (1.97 in) or more of precipitation in 54 years, most in 1979 with 10.
Charleston: days with a maximum temperature at or above 30 C (86 F) in 48 years, most in 1921 with 156.
17 fixed thresholds have at least one qualifying day at Charleston.

Days at or above 30 C (86 F)

48 years with a qualifying day

Days per year at Charleston with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 156 in 1921.

Days at or above 30 C (86 F) per year at Charleston
Year	Days	Decade average
1912	155	126.2
1913	115	126.2
1914	127	126.2
1915	120	126.2
1919	114	126.2
1920	124	140
1921	156	140
1952	128	131
1953	145	131
1954	138	131
1955	129	131
1956	133	131
1957	121	131
1958	114	131
1959	140	131
1960	132	121.5
1961	110	121.5
1962	149	121.5
1963	144	121.5
1964	113	121.5
1965	135	121.5
1966	110	121.5
1967	96	121.5
1968	111	121.5
1969	115	121.5
1970	120	114.9
1971	113	114.9
1972	129	114.9
1973	123	114.9
1974	93	114.9
1976	97	114.9
1977	139	114.9
1978	112	114.9
1979	108	114.9
1980	121	110
1981	118	110
1989	91	110
1990	109	102.1
1991	101	102.1
1992	68	102.1
1993	107	102.1
1994	101	102.1
1995	111	102.1
1996	102	102.1
1997	80	102.1
1998	131	102.1
1999	111	102.1
2000	123	123

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

First to last qualifying date each year at Charleston
Year	First date	Last date
1912	1912-04-02	1912-10-31
1913	1913-04-18	1913-10-10
1914	1914-04-06	1914-11-04
1915	1915-04-17	1915-10-17
1919	1919-04-07	1919-10-02
1920	1920-04-17	1920-10-20
1921	1921-03-15	1921-10-26
1952	1952-04-30	1952-10-02
1953	1953-04-09	1953-10-26
1954	1954-04-06	1954-10-12
1955	1955-04-18	1955-11-15
1956	1956-04-28	1956-10-20
1957	1957-04-03	1957-09-22
1958	1958-04-24	1958-10-10
1959	1959-04-07	1959-10-09
1960	1960-04-07	1960-10-05
1961	1961-05-06	1961-10-31
1962	1962-04-11	1962-10-16
1963	1963-03-30	1963-10-28
1964	1964-05-17	1964-09-28
1965	1965-04-10	1965-10-18
1966	1966-04-01	1966-09-27
1967	1967-03-31	1967-10-16
1968	1968-04-19	1968-10-15
1969	1969-04-17	1969-10-13
1970	1970-04-30	1970-10-04
1971	1971-04-17	1971-10-29
1972	1972-04-13	1972-10-19
1973	1973-05-11	1973-10-13
1974	1974-05-04	1974-09-21
1976	1976-04-24	1976-10-05
1977	1977-04-11	1977-10-02
1978	1978-04-06	1978-10-23
1979	1979-05-08	1979-10-22
1980	1980-04-22	1980-10-11
1981	1981-04-11	1981-10-06
1989	1989-04-22	1989-10-03
1990	1990-04-25	1990-10-08
1991	1991-05-14	1991-09-19
1992	1992-04-25	1992-09-21
1993	1993-05-06	1993-10-07
1994	1994-04-21	1994-10-01
1995	1995-04-11	1995-10-11
1996	1996-05-06	1996-09-26
1997	1997-05-18	1997-10-12
1998	1998-03-30	1998-10-31
1999	1999-04-24	1999-09-29
2000	2000-04-20	2000-11-01

Every Fixed Threshold

Fixed thresholds at Charleston
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	48	156	1921	123
35 C (95 F): Days	46	95	1954	44
40 C (104 F): Days	7	8	1954	3
90 F (32.2 C): Days	48	134	1921	85
100 F (37.8 C): Days	30	41	1954	15
0 C (32 F): Ice days (max	39	14	1989	5
0 C (32 F): Frost days (min	44	91	1963	65
-10 C (14 F): Days with min	30	15	1963	1
-20 C (-4 F): Days with min	3	1	1962	1
20 C (68 F): Tropical nights (min	44	107	1921	66
25 C (77 F): Days with min	21	8	1980	2
10 mm (0.39 in): Days with 10 mm or more rain	55	62	1974	43
25 mm (0.98 in): Days with 25 mm or more rain	55	28	1957	22
50 mm (1.97 in): Days with 50 mm or more rain	54	10	1979	4
100 mm (3.94 in): Days with 100 mm or more rain	16	3	1991	3
10 cm (3.9 in): Days with 10 cm or more snowfall	8	2	1948	1
25 cm (9.8 in): Days with 25 cm or more snowfall	1	1	1968	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1912.

Download the Data

Data for Charleston 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).

Charleston Threshold Days by Year (USC00221606)

Key Facts for Charleston Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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