Blackwater Refuge Threshold Days by Year (USC00180915)
17 fixed thresholds counted per year at Blackwater Refuge (USC00180915): hot days, frost, tropical nights and heavy rain, with the most days in a year.
Key Facts for Blackwater Refuge Thresholds
- Blackwater Refuge: days with 10 mm (0.39 in) or more of precipitation in 33 years, most in 1948 with 57.
- Blackwater Refuge: days with 25 mm (0.98 in) or more of precipitation in 33 years, most in 1952 with 21.
- Blackwater Refuge: days with a maximum temperature at or above 30 C (86 F) in 32 years, most in 1959 with 76.
- Blackwater Refuge: days with a maximum temperature at or above 90 F (32.2 C) in 32 years, most in 1963 with 44.
- 17 fixed thresholds have at least one qualifying day at Blackwater Refuge.
Days at or above 30 C (86 F)
32 years with a qualifying day| Year | Days | Decade average |
|---|---|---|
| 1942 | 54 | 42.8 |
| 1943 | 73 | 42.8 |
| 1944 | 51 | 42.8 |
| 1945 | 24 | 42.8 |
| 1946 | 9 | 42.8 |
| 1947 | 45 | 42.8 |
| 1948 | 57 | 42.8 |
| 1949 | 29 | 42.8 |
| 1950 | 31 | 55.3 |
| 1951 | 43 | 55.3 |
| 1952 | 69 | 55.3 |
| 1954 | 46 | 55.3 |
| 1955 | 64 | 55.3 |
| 1956 | 54 | 55.3 |
| 1957 | 63 | 55.3 |
| 1958 | 52 | 55.3 |
| 1959 | 76 | 55.3 |
| 1960 | 62 | 55.7 |
| 1961 | 71 | 55.7 |
| 1962 | 48 | 55.7 |
| 1963 | 76 | 55.7 |
| 1964 | 57 | 55.7 |
| 1965 | 52 | 55.7 |
| 1966 | 60 | 55.7 |
| 1967 | 23 | 55.7 |
| 1968 | 37 | 55.7 |
| 1969 | 71 | 55.7 |
| 1970 | 76 | 62 |
| 1971 | 55 | 62 |
| 1973 | 63 | 62 |
| 1975 | 53 | 62 |
| 1976 | 63 | 62 |
| Year | First date | Last date |
|---|---|---|
| 1942 | 1942-05-02 | 1942-09-21 |
| 1943 | 1943-05-08 | 1943-09-17 |
| 1944 | 1944-05-10 | 1944-09-14 |
| 1945 | 1945-06-11 | 1945-09-11 |
| 1946 | 1946-06-18 | 1946-09-09 |
| 1947 | 1947-05-18 | 1947-09-16 |
| 1948 | 1948-06-12 | 1948-09-21 |
| 1949 | 1949-05-19 | 1949-09-06 |
| 1950 | 1950-05-06 | 1950-09-10 |
| 1951 | 1951-06-01 | 1951-09-03 |
| 1952 | 1952-06-06 | 1952-09-19 |
| 1954 | 1954-06-12 | 1954-10-13 |
| 1955 | 1955-04-19 | 1955-09-21 |
| 1956 | 1956-05-13 | 1956-09-18 |
| 1957 | 1957-04-21 | 1957-09-14 |
| 1958 | 1958-06-09 | 1958-09-18 |
| 1959 | 1959-05-12 | 1959-10-05 |
| 1960 | 1960-04-24 | 1960-09-09 |
| 1961 | 1961-04-25 | 1961-09-26 |
| 1962 | 1962-05-07 | 1962-09-12 |
| 1963 | 1963-05-09 | 1963-10-18 |
| 1964 | 1964-05-08 | 1964-09-12 |
| 1965 | 1965-05-03 | 1965-09-22 |
| 1966 | 1966-06-10 | 1966-09-07 |
| 1967 | 1967-06-10 | 1967-08-27 |
| 1968 | 1968-06-16 | 1968-08-26 |
| 1969 | 1969-05-29 | 1969-09-15 |
| 1970 | 1970-05-09 | 1970-09-26 |
| 1971 | 1971-06-05 | 1971-09-12 |
| 1973 | 1973-06-04 | 1973-09-30 |
| 1975 | 1975-05-21 | 1975-08-30 |
| 1976 | 1976-04-16 | 1976-09-15 |
Every Fixed Threshold
| Threshold | Years with a qualifying day | Most days in a year | Year | Latest year days |
|---|---|---|---|---|
| 30 C (86 F): Days | 32 | 76 | 1959 | 63 |
| 35 C (95 F): Days | 21 | 12 | 1963 | 4 |
| 90 F (32.2 C): Days | 32 | 44 | 1963 | 26 |
| 100 F (37.8 C): Days | 2 | 2 | 1959 | 2 |
| 0 C (32 F): Ice days (max | 31 | 24 | 1958 | 3 |
| 0 C (32 F): Frost days (min | 32 | 106 | 1969 | 76 |
| -10 C (14 F): Days with min | 28 | 15 | 1968 | 6 |
| -20 C (-4 F): Days with min | 3 | 2 | 1961 | 1 |
| 20 C (68 F): Tropical nights (min | 32 | 89 | 1959 | 39 |
| 25 C (77 F): Days with min | 24 | 11 | 1955 | 1 |
| 10 mm (0.39 in): Days with 10 mm or more rain | 33 | 57 | 1948 | 37 |
| 25 mm (0.98 in): Days with 25 mm or more rain | 33 | 21 | 1952 | 13 |
| 50 mm (1.97 in): Days with 50 mm or more rain | 27 | 6 | 1945 | 1 |
| 100 mm (3.94 in): Days with 100 mm or more rain | 8 | 2 | 1945 | 1 |
| 200 mm (7.87 in): Days with 200 mm or more rain | 1 | 1 | 1955 | 1 |
| 10 cm (3.9 in): Days with 10 cm or more snowfall | 15 | 5 | 1958 | 1 |
| 25 cm (9.8 in): Days with 25 cm or more snowfall | 1 | 1 | 1966 | 1 |
Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1942.
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).