Rock Hall Threshold Days by Year (USC00187700)
17 fixed thresholds counted per year at Rock Hall (USC00187700): hot days, frost, tropical nights and heavy rain, with the most days in a year.
Key Facts for Rock Hall Thresholds
- Rock Hall: days with 10 mm (0.39 in) or more of precipitation in 41 years, most in 1937 with 49.
- Rock Hall: days with 25 mm (0.98 in) or more of precipitation in 41 years, most in 1937 with 17.
- Rock Hall: days with a maximum temperature at or above 30 C (86 F) in 40 years, most in 1943 with 77.
- Rock Hall: days with a maximum temperature at or above 90 F (32.2 C) in 40 years, most in 1943 with 55.
- 17 fixed thresholds have at least one qualifying day at Rock Hall.
Days at or above 30 C (86 F)
40 years with a qualifying day| Year | Days | Decade average |
|---|---|---|
| 1899 | 48 | 48 |
| 1900 | 72 | 61.5 |
| 1901 | 51 | 61.5 |
| 1922 | 54 | 53.1 |
| 1923 | 55 | 53.1 |
| 1924 | 43 | 53.1 |
| 1925 | 73 | 53.1 |
| 1926 | 50 | 53.1 |
| 1927 | 42 | 53.1 |
| 1928 | 49 | 53.1 |
| 1929 | 59 | 53.1 |
| 1930 | 75 | 65.5 |
| 1931 | 76 | 65.5 |
| 1932 | 69 | 65.5 |
| 1933 | 73 | 65.5 |
| 1934 | 70 | 65.5 |
| 1935 | 58 | 65.5 |
| 1936 | 62 | 65.5 |
| 1937 | 51 | 65.5 |
| 1938 | 46 | 65.5 |
| 1939 | 75 | 65.5 |
| 1942 | 63 | 62 |
| 1943 | 77 | 62 |
| 1944 | 75 | 62 |
| 1945 | 61 | 62 |
| 1946 | 43 | 62 |
| 1949 | 53 | 62 |
| 1950 | 37 | 54.3 |
| 1951 | 54 | 54.3 |
| 1952 | 50 | 54.3 |
| 1953 | 52 | 54.3 |
| 1954 | 60 | 54.3 |
| 1955 | 56 | 54.3 |
| 1956 | 47 | 54.3 |
| 1957 | 70 | 54.3 |
| 1958 | 42 | 54.3 |
| 1959 | 75 | 54.3 |
| 1964 | 62 | 63.3 |
| 1965 | 54 | 63.3 |
| 1966 | 74 | 63.3 |
| Year | First date | Last date |
|---|---|---|
| 1899 | 1899-05-28 | 1899-09-09 |
| 1900 | 1900-05-13 | 1900-09-27 |
| 1901 | 1901-06-12 | 1901-09-15 |
| 1922 | 1922-04-10 | 1922-10-05 |
| 1923 | 1923-05-29 | 1923-09-25 |
| 1924 | 1924-06-18 | 1924-09-02 |
| 1925 | 1925-05-23 | 1925-09-21 |
| 1926 | 1926-05-07 | 1926-10-05 |
| 1927 | 1927-06-09 | 1927-10-02 |
| 1928 | 1928-05-04 | 1928-09-13 |
| 1929 | 1929-04-06 | 1929-09-13 |
| 1930 | 1930-05-01 | 1930-09-27 |
| 1931 | 1931-05-29 | 1931-10-08 |
| 1932 | 1932-05-07 | 1932-09-23 |
| 1933 | 1933-05-20 | 1933-09-27 |
| 1934 | 1934-05-05 | 1934-09-22 |
| 1935 | 1935-05-28 | 1935-09-21 |
| 1936 | 1936-05-08 | 1936-09-13 |
| 1937 | 1937-05-22 | 1937-09-04 |
| 1938 | 1938-06-07 | 1938-09-15 |
| 1939 | 1939-05-06 | 1939-10-10 |
| 1942 | 1942-04-06 | 1942-09-19 |
| 1943 | 1943-05-07 | 1943-09-16 |
| 1944 | 1944-05-15 | 1944-09-13 |
| 1945 | 1945-03-29 | 1945-09-30 |
| 1946 | 1946-05-25 | 1946-09-18 |
| 1949 | 1949-05-07 | 1949-09-06 |
| 1950 | 1950-06-07 | 1950-09-08 |
| 1951 | 1951-06-01 | 1951-10-06 |
| 1952 | 1952-06-06 | 1952-09-14 |
| 1953 | 1953-06-06 | 1953-09-29 |
| 1954 | 1954-06-08 | 1954-10-13 |
| 1955 | 1955-05-05 | 1955-09-20 |
| 1956 | 1956-05-13 | 1956-09-17 |
| 1957 | 1957-04-21 | 1957-09-22 |
| 1958 | 1958-06-09 | 1958-09-26 |
| 1959 | 1959-05-07 | 1959-10-06 |
| 1964 | 1964-05-08 | 1964-09-12 |
| 1965 | 1965-05-03 | 1965-09-23 |
| 1966 | 1966-06-04 | 1966-09-06 |
Every Fixed Threshold
| Threshold | Years with a qualifying day | Most days in a year | Year | Latest year days |
|---|---|---|---|---|
| 30 C (86 F): Days | 40 | 77 | 1943 | 74 |
| 35 C (95 F): Days | 34 | 24 | 1930 | 10 |
| 40 C (104 F): Days | 2 | 2 | 1930 | 1 |
| 90 F (32.2 C): Days | 40 | 55 | 1943 | 40 |
| 100 F (37.8 C): Days | 11 | 8 | 1930 | 1 |
| 0 C (32 F): Ice days (max | 39 | 23 | 1899 | 10 |
| 0 C (32 F): Frost days (min | 40 | 124 | 1926 | 86 |
| -10 C (14 F): Days with min | 39 | 24 | 1936 | 6 |
| -20 C (-4 F): Days with min | 3 | 3 | 1899 | 1 |
| 20 C (68 F): Tropical nights (min | 40 | 59 | 1900 | 41 |
| 25 C (77 F): Days with min | 21 | 6 | 1943 | 1 |
| 10 mm (0.39 in): Days with 10 mm or more rain | 41 | 49 | 1937 | 26 |
| 25 mm (0.98 in): Days with 25 mm or more rain | 41 | 17 | 1937 | 10 |
| 50 mm (1.97 in): Days with 50 mm or more rain | 34 | 4 | 1900 | 3 |
| 100 mm (3.94 in): Days with 100 mm or more rain | 4 | 1 | 1928 | 1 |
| 10 cm (3.9 in): Days with 10 cm or more snowfall | 14 | 3 | 1899 | 3 |
| 25 cm (9.8 in): Days with 25 cm or more snowfall | 3 | 2 | 1958 | 2 |
Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1899.
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).