Heart Mtn Threshold Days by Year (USC00484411)
15 fixed thresholds counted per year at Heart Mtn (USC00484411): hot days, frost, tropical nights and heavy rain, with the most days in a year.
Key Facts for Heart Mtn Thresholds
- Heart Mtn: days with a maximum temperature at or above 30 C (86 F) in 58 years, most in 1988 with 66.
- Heart Mtn: days with a maximum temperature at or below 0 C (32 F) in 58 years, most in 1978 with 76.
- Heart Mtn: nights with a minimum temperature at or below 0 C (32 F) in 58 years, most in 1970 with 218.
- Heart Mtn: nights with a minimum temperature at or below -10 C (14 F) in 58 years, most in 1978 with 98.
- 15 fixed thresholds have at least one qualifying day at Heart Mtn.
Days at or above 30 C (86 F)
58 years with a qualifying day| Year | Days | Decade average |
|---|---|---|
| 1943 | 38 | 38 |
| 1950 | 27 | 39.8 |
| 1951 | 25 | 39.8 |
| 1952 | 42 | 39.8 |
| 1953 | 53 | 39.8 |
| 1954 | 57 | 39.8 |
| 1955 | 56 | 39.8 |
| 1956 | 45 | 39.8 |
| 1957 | 37 | 39.8 |
| 1958 | 26 | 39.8 |
| 1959 | 30 | 39.8 |
| 1961 | 49 | 35.9 |
| 1962 | 24 | 35.9 |
| 1963 | 38 | 35.9 |
| 1964 | 41 | 35.9 |
| 1965 | 17 | 35.9 |
| 1966 | 51 | 35.9 |
| 1967 | 32 | 35.9 |
| 1968 | 26 | 35.9 |
| 1969 | 45 | 35.9 |
| 1970 | 54 | 37.9 |
| 1971 | 49 | 37.9 |
| 1972 | 25 | 37.9 |
| 1973 | 40 | 37.9 |
| 1974 | 43 | 37.9 |
| 1975 | 29 | 37.9 |
| 1976 | 42 | 37.9 |
| 1977 | 39 | 37.9 |
| 1978 | 35 | 37.9 |
| 1979 | 23 | 37.9 |
| 1980 | 25 | 42.6 |
| 1981 | 47 | 42.6 |
| 1982 | 25 | 42.6 |
| 1983 | 46 | 42.6 |
| 1984 | 56 | 42.6 |
| 1985 | 43 | 42.6 |
| 1986 | 42 | 42.6 |
| 1987 | 44 | 42.6 |
| 1988 | 66 | 42.6 |
| 1989 | 32 | 42.6 |
| 1990 | 28 | 27.8 |
| 1991 | 39 | 27.8 |
| 1992 | 14 | 27.8 |
| 1993 | 6 | 27.8 |
| 1994 | 30 | 27.8 |
| 1995 | 36 | 27.8 |
| 1996 | 39 | 27.8 |
| 1997 | 16 | 27.8 |
| 1998 | 38 | 27.8 |
| 1999 | 32 | 27.8 |
| 2000 | 43 | 41.1 |
| 2001 | 45 | 41.1 |
| 2002 | 38 | 41.1 |
| 2003 | 48 | 41.1 |
| 2004 | 17 | 41.1 |
| 2005 | 41 | 41.1 |
| 2006 | 46 | 41.1 |
| 2007 | 51 | 41.1 |
| Year | First date | Last date |
|---|---|---|
| 1943 | 1943-06-17 | 1943-09-17 |
| 1950 | 1950-06-30 | 1950-09-06 |
| 1951 | 1951-05-27 | 1951-09-10 |
| 1952 | 1952-06-05 | 1952-09-26 |
| 1953 | 1953-06-11 | 1953-09-30 |
| 1954 | 1954-05-19 | 1954-09-26 |
| 1955 | 1955-05-20 | 1955-09-14 |
| 1956 | 1956-05-20 | 1956-09-26 |
| 1957 | 1957-06-03 | 1957-09-07 |
| 1958 | 1958-05-20 | 1958-09-08 |
| 1959 | 1959-06-06 | 1959-09-13 |
| 1961 | 1961-06-07 | 1961-08-25 |
| 1962 | 1962-06-25 | 1962-08-26 |
| 1963 | 1963-06-08 | 1963-08-26 |
| 1964 | 1964-05-20 | 1964-08-18 |
| 1965 | 1965-07-07 | 1965-08-13 |
| 1966 | 1966-05-04 | 1966-09-23 |
| 1967 | 1967-05-22 | 1967-09-06 |
| 1968 | 1968-06-02 | 1968-08-08 |
| 1969 | 1969-05-24 | 1969-09-03 |
| 1970 | 1970-05-17 | 1970-09-04 |
| 1971 | 1971-06-16 | 1971-09-13 |
| 1972 | 1972-05-16 | 1972-08-30 |
| 1973 | 1973-05-31 | 1973-08-30 |
| 1974 | 1974-06-03 | 1974-09-26 |
| 1975 | 1975-06-24 | 1975-09-15 |
| 1976 | 1976-06-06 | 1976-09-06 |
| 1977 | 1977-06-01 | 1977-09-15 |
| 1978 | 1978-05-15 | 1978-09-10 |
| 1979 | 1979-06-12 | 1979-09-16 |
| 1980 | 1980-04-21 | 1980-09-02 |
| 1981 | 1981-06-25 | 1981-09-19 |
| 1982 | 1982-05-26 | 1982-09-09 |
| 1983 | 1983-05-26 | 1983-09-08 |
| 1984 | 1984-05-15 | 1984-09-19 |
| 1985 | 1985-05-02 | 1985-09-04 |
| 1986 | 1986-05-20 | 1986-08-30 |
| 1987 | 1987-04-28 | 1987-09-25 |
| 1988 | 1988-05-13 | 1988-08-30 |
| 1989 | 1989-06-15 | 1989-09-17 |
| 1990 | 1990-06-23 | 1990-09-12 |
| 1991 | 1991-06-11 | 1991-09-02 |
| 1992 | 1992-05-18 | 1992-09-23 |
| 1993 | 1993-05-13 | 1993-08-16 |
| 1994 | 1994-06-20 | 1994-09-09 |
| 1995 | 1995-06-13 | 1995-09-03 |
| 1996 | 1996-06-08 | 1996-09-04 |
| 1997 | 1997-06-04 | 1997-08-31 |
| 1998 | 1998-07-04 | 1998-09-18 |
| 1999 | 1999-06-19 | 1999-08-30 |
| 2000 | 2000-06-05 | 2000-09-16 |
| 2001 | 2001-05-12 | 2001-09-04 |
| 2002 | 2002-05-20 | 2002-09-04 |
| 2003 | 2003-05-28 | 2003-09-05 |
| 2004 | 2004-06-06 | 2004-09-01 |
| 2005 | 2005-06-17 | 2005-09-09 |
| 2006 | 2006-05-18 | 2006-09-01 |
| 2007 | 2007-05-12 | 2007-09-04 |
Every Fixed Threshold
| Threshold | Years with a qualifying day | Most days in a year | Year | Latest year days |
|---|---|---|---|---|
| 30 C (86 F): Days | 58 | 66 | 1988 | 51 |
| 35 C (95 F): Days | 44 | 17 | 1954 | 7 |
| 90 F (32.2 C): Days | 57 | 46 | 1988 | 30 |
| 100 F (37.8 C): Days | 5 | 2 | 1954 | 1 |
| 0 C (32 F): Ice days (max | 58 | 76 | 1978 | 57 |
| 0 C (32 F): Frost days (min | 58 | 218 | 1970 | 157 |
| -10 C (14 F): Days with min | 58 | 98 | 1978 | 62 |
| -20 C (-4 F): Days with min | 58 | 34 | 1985 | 9 |
| -30 C (-22 F): Days with min | 29 | 10 | 1972 | 2 |
| 20 C (68 F): Tropical nights (min | 5 | 2 | 1954 | 1 |
| 10 mm (0.39 in): Days with 10 mm or more rain | 57 | 9 | 1975 | 7 |
| 25 mm (0.98 in): Days with 25 mm or more rain | 25 | 3 | 1987 | 2 |
| 50 mm (1.97 in): Days with 50 mm or more rain | 2 | 1 | 1988 | 1 |
| 10 cm (3.9 in): Days with 10 cm or more snowfall | 25 | 7 | 1973 | 5 |
| 25 cm (9.8 in): Days with 25 cm or more snowfall | 3 | 1 | 1992 | 1 |
Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1943.
Download the Data
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 . Last revised (2025-12-31).