Blackwater Dam Threshold Days by Year (USC00270741)
16 fixed thresholds counted per year at Blackwater Dam (USC00270741): hot days, frost, tropical nights and heavy rain, with the most days in a year.
Key Facts for Blackwater Dam Thresholds
- Blackwater Dam: days with 10 mm (0.39 in) or more of precipitation in 42 years, most in 1983 with 51.
- Blackwater Dam: days with 25 mm (0.98 in) or more of precipitation in 42 years, most in 1983 with 18.
- Blackwater Dam: days with 10 cm (3.9 in) or more of snowfall in 42 years, most in 1956 with 14.
- Blackwater Dam: days with a maximum temperature at or above 30 C (86 F) in 40 years, most in 1959 with 39.
- 16 fixed thresholds have at least one qualifying day at Blackwater Dam.
Days at or above 30 C (86 F)
40 years with a qualifying day| Year | Days | Decade average |
|---|---|---|
| 1949 | 34 | 34 |
| 1950 | 17 | 23 |
| 1951 | 6 | 23 |
| 1953 | 28 | 23 |
| 1955 | 36 | 23 |
| 1956 | 12 | 23 |
| 1957 | 30 | 23 |
| 1958 | 16 | 23 |
| 1959 | 39 | 23 |
| 1960 | 12 | 17.3 |
| 1961 | 21 | 17.3 |
| 1962 | 13 | 17.3 |
| 1963 | 21 | 17.3 |
| 1964 | 21 | 17.3 |
| 1965 | 25 | 17.3 |
| 1966 | 18 | 17.3 |
| 1967 | 11 | 17.3 |
| 1968 | 15 | 17.3 |
| 1969 | 16 | 17.3 |
| 1970 | 23 | 19.3 |
| 1971 | 24 | 19.3 |
| 1972 | 11 | 19.3 |
| 1973 | 22 | 19.3 |
| 1974 | 19 | 19.3 |
| 1975 | 21 | 19.3 |
| 1976 | 19 | 19.3 |
| 1977 | 17 | 19.3 |
| 1978 | 19 | 19.3 |
| 1979 | 18 | 19.3 |
| 1980 | 21 | 19.1 |
| 1981 | 7 | 19.1 |
| 1982 | 9 | 19.1 |
| 1983 | 38 | 19.1 |
| 1984 | 23 | 19.1 |
| 1985 | 19 | 19.1 |
| 1986 | 8 | 19.1 |
| 1987 | 18 | 19.1 |
| 1988 | 33 | 19.1 |
| 1989 | 15 | 19.1 |
| 1990 | 17 | 17 |
| Year | First date | Last date |
|---|---|---|
| 1949 | 1949-05-05 | 1949-08-28 |
| 1950 | 1950-06-07 | 1950-08-28 |
| 1951 | 1951-05-16 | 1951-07-26 |
| 1953 | 1953-05-10 | 1953-10-04 |
| 1955 | 1955-05-04 | 1955-09-19 |
| 1956 | 1956-06-01 | 1956-09-06 |
| 1957 | 1957-04-28 | 1957-09-23 |
| 1958 | 1958-07-01 | 1958-09-16 |
| 1959 | 1959-05-22 | 1959-09-25 |
| 1960 | 1960-06-06 | 1960-09-09 |
| 1961 | 1961-05-15 | 1961-09-12 |
| 1962 | 1962-04-28 | 1962-08-28 |
| 1963 | 1963-06-25 | 1963-10-08 |
| 1964 | 1964-05-24 | 1964-09-12 |
| 1965 | 1965-05-11 | 1965-09-23 |
| 1966 | 1966-06-07 | 1966-08-20 |
| 1967 | 1967-06-04 | 1967-08-19 |
| 1968 | 1968-06-07 | 1968-08-26 |
| 1969 | 1969-04-29 | 1969-09-02 |
| 1970 | 1970-05-11 | 1970-09-23 |
| 1971 | 1971-06-08 | 1971-09-06 |
| 1972 | 1972-05-29 | 1972-08-26 |
| 1973 | 1973-06-12 | 1973-09-05 |
| 1974 | 1974-05-16 | 1974-08-23 |
| 1975 | 1975-05-21 | 1975-08-12 |
| 1976 | 1976-04-18 | 1976-09-15 |
| 1977 | 1977-05-18 | 1977-08-31 |
| 1978 | 1978-05-21 | 1978-09-22 |
| 1979 | 1979-05-10 | 1979-08-06 |
| 1980 | 1980-06-25 | 1980-09-03 |
| 1981 | 1981-05-26 | 1981-08-12 |
| 1982 | 1982-07-08 | 1982-07-20 |
| 1983 | 1983-06-13 | 1983-09-21 |
| 1984 | 1984-05-24 | 1984-08-31 |
| 1985 | 1985-05-12 | 1985-08-16 |
| 1986 | 1986-05-19 | 1986-07-27 |
| 1987 | 1987-05-30 | 1987-08-20 |
| 1988 | 1988-05-29 | 1988-08-16 |
| 1989 | 1989-05-19 | 1989-09-11 |
| 1990 | 1990-04-28 | 1990-08-28 |
Every Fixed Threshold
| Threshold | Years with a qualifying day | Most days in a year | Year | Latest year days |
|---|---|---|---|---|
| 30 C (86 F): Days | 40 | 39 | 1959 | 17 |
| 35 C (95 F): Days | 15 | 6 | 1955 | 2 |
| 90 F (32.2 C): Days | 39 | 21 | 1955 | 7 |
| 0 C (32 F): Ice days (max | 40 | 72 | 1970 | 32 |
| 0 C (32 F): Frost days (min | 40 | 198 | 1978 | 133 |
| -10 C (14 F): Days with min | 40 | 86 | 1989 | 43 |
| -20 C (-4 F): Days with min | 39 | 25 | 1963 | 6 |
| -30 C (-22 F): Days with min | 5 | 7 | 1971 | 2 |
| 20 C (68 F): Tropical nights (min | 27 | 7 | 1988 | 2 |
| 10 mm (0.39 in): Days with 10 mm or more rain | 42 | 51 | 1983 | 41 |
| 25 mm (0.98 in): Days with 25 mm or more rain | 42 | 18 | 1983 | 16 |
| 50 mm (1.97 in): Days with 50 mm or more rain | 32 | 5 | 1977 | 5 |
| 100 mm (3.94 in): Days with 100 mm or more rain | 4 | 1 | 1960 | 1 |
| 10 cm (3.9 in): Days with 10 cm or more snowfall | 42 | 14 | 1956 | 7 |
| 25 cm (9.8 in): Days with 25 cm or more snowfall | 23 | 3 | 1972 | 1 |
| 50 cm (19.7 in): Days with 50 cm or more snowfall | 1 | 1 | 1969 | 1 |
Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1949.
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).