| YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
| 1899 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1900 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1901 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1902 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1903 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1904 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1905 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1906 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1907 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1908 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1909 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1910 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1911 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1912 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| 1913 | ----- | z | ----- | z | ----- | z | 50.86 | a | 60.30 | a | 66.72 | c | 71.89 | 74.38 | c | 68.05 | k | 47.31 | j | 43.24 | a | 29.07 | c | 56.64 | e | |
| 1914 | 31.63 | 32.11 | 43.17 | a | 50.32 | 60.75 | a | 62.66 | e | 73.07 | h | 73.11 | d | 61.38 | b | 53.76 | b | 43.10 | e | 24.69 | d | 48.79 | a | |||
| 1915 | 23.73 | a | 35.65 | a | 44.12 | a | 58.16 | b | 55.75 | c | 62.67 | g | 73.38 | c | 75.55 | b | 60.92 | 54.56 | d | 40.91 | a | 30.66 | b | 50.31 | a | |
| 1916 | 25.37 | d | 32.41 | a | 43.22 | b | 50.67 | a | 52.29 | 63.58 | 75.29 | 72.23 | 62.92 | 49.30 | a | 35.03 | 25.68 | c | 49.00 | |||||||
| 1917 | 18.44 | m | 25.81 | a | 28.95 | a | 43.96 | b | 52.35 | 64.76 | a | 77.17 | d | 71.50 | h | 63.93 | 51.90 | 42.07 | 39.04 | c | 48.99 | b | ||||
| 1918 | 30.50 | b | 28.25 | 43.22 | a | 46.45 | 56.02 | g | 74.05 | i | 73.64 | f | 71.64 | i | 65.93 | 54.39 | 40.64 | a | 30.30 | a | 42.46 | d | ||||
| 1919 | 30.67 | a | 32.56 | a | 42.05 | 51.87 | 62.23 | 71.72 | 78.21 | e | 75.97 | a | 66.42 | 45.77 | ----- | z | ----- | z | 55.74 | b | ||||||
| 1920 | ----- | z | ----- | z | ----- | z | 42.45 | a | 57.16 | 66.80 | 77.26 | 73.65 | 62.93 | 47.31 | b | 38.17 | 29.56 | 55.03 | c | |||||||
| 1921 | 31.62 | b | 33.96 | 43.85 | 45.87 | 57.16 | 69.07 | 76.03 | 72.87 | 60.28 | 55.89 | 43.97 | 33.11 | 51.97 | ||||||||||||
| 1922 | 19.89 | 26.89 | 33.00 | a | 43.72 | 58.66 | b | 72.24 | a | 74.08 | 74.53 | 66.62 | 54.06 | 37.60 | a | 30.48 | a | 49.31 | ||||||||
| 1923 | 32.08 | 23.83 | a | 36.81 | 48.26 | a | 58.88 | b | 64.43 | a | 77.14 | b | 70.66 | 63.72 | a | 47.03 | a | 41.62 | 27.07 | a | 49.29 | |||||
| 1924 | 19.21 | 36.22 | 36.12 | a | 49.07 | a | 61.56 | 66.97 | 73.63 | 69.34 | 59.05 | 47.11 | 37.42 | 19.66 | b | 47.95 | ||||||||||
| 1925 | 24.48 | 37.46 | a | 43.19 | 51.13 | 62.44 | 64.67 | 76.63 | 70.55 | 62.05 | 49.92 | 37.25 | 33.71 | 51.12 | ||||||||||||
| 1926 | 25.27 | 35.84 | 42.74 | 54.18 | 59.45 | 69.90 | 75.02 | 72.56 | 59.43 | 52.10 | 43.18 | 26.90 | 51.38 | |||||||||||||
| 1927 | 28.24 | 33.57 | 38.06 | 46.63 | 53.61 | 66.33 | 73.50 | 71.21 | 62.12 | a | 52.05 | 42.74 | a | 24.85 | a | 49.41 | ||||||||||
| 1928 | 25.95 | a | 32.03 | 43.02 | 46.25 | 63.02 | 63.70 | 75.35 | 71.05 | 63.08 | 50.40 | a | 38.50 | 22.07 | a | 49.53 | ||||||||||
| 1929 | 21.23 | 24.00 | 38.31 | 45.48 | 56.73 | 64.30 | 75.89 | 74.87 | 58.93 | 51.00 | 35.12 | 33.79 | 48.30 | |||||||||||||
| 1930 | 17.84 | b | 36.11 | a | 41.03 | 54.55 | 54.11 | c | 66.73 | 77.56 | 73.73 | 63.45 | b | 48.64 | b | 32.43 | 18.38 | b | 48.71 | |||||||
| 1931 | 18.77 | 32.32 | 39.30 | a | 50.95 | 58.81 | 72.37 | 79.12 | a | 76.05 | b | 63.62 | a | 53.52 | 34.14 | a | 23.58 | a | 50.21 | |||||||
| 1932 | 18.13 | a | 26.55 | a | 37.32 | 49.29 | a | 60.19 | 66.67 | 74.31 | 72.02 | b | 64.29 | d | 49.50 | b | 40.65 | 19.36 | c | 48.19 | ||||||
| 1933 | 22.50 | 16.20 | 36.02 | 46.17 | 54.41 | b | 73.88 | 79.06 | 71.95 | a | 65.15 | 57.10 | a | 40.52 | 35.50 | 49.87 | ||||||||||
| 1934 | 33.52 | 40.68 | 48.09 | b | 55.87 | 66.10 | 67.37 | 76.73 | 75.72 | b | 61.55 | a | 54.50 | b | 42.52 | 32.90 | 54.63 | |||||||||
| 1935 | 31.14 | b | 35.57 | 40.43 | a | 50.92 | 55.42 | a | 70.52 | c | 76.34 | 73.90 | a | 66.98 | b | 52.07 | a | 35.40 | 30.65 | a | 51.61 | |||||
| 1936 | 27.56 | 31.36 | 39.72 | b | 52.97 | 63.07 | a | 71.11 | c | 77.60 | a | 74.27 | c | 62.58 | d | 53.89 | i | 37.73 | d | 33.00 | 51.91 | a | ||||
| 1937 | 15.21 | e | 27.56 | d | 38.83 | d | 46.15 | c | 62.36 | f | 66.19 | c | 76.13 | a | 75.18 | 66.71 | b | 54.95 | a | 42.05 | 35.03 | 49.45 | a | |||
| 1938 | 36.62 | g | 38.30 | 42.22 | b | 52.17 | a | 57.85 | d | 70.95 | 74.65 | 75.20 | c | 69.48 | b | 52.79 | 31.60 | 32.97 | 54.38 | a | ||||||
| 1939 | 27.97 | a | 22.77 | 39.11 | 51.86 | a | 60.48 | 64.78 | 74.05 | a | 70.82 | c | 61.95 | 50.39 | 40.67 | 35.00 | 49.99 | |||||||||
| 1940 | 30.02 | 37.98 | 43.98 | 50.97 | 62.89 | 70.83 | 75.73 | 74.21 | 63.47 | 52.27 | 35.37 | 30.68 | 52.37 | |||||||||||||
| 1941 | 28.00 | 34.39 | 42.58 | 48.30 | b | 60.87 | 64.85 | 74.37 | 71.32 | 58.65 | 49.85 | 39.32 | 33.08 | 50.47 | ||||||||||||
| 1942 | 18.12 | a | 23.12 | 32.19 | 51.27 | 53.85 | 63.82 | 76.05 | 71.71 | ----- | z | ----- | z | 39.29 | i | 31.98 | e | 46.90 | c | |||||||
| 1943 | 30.15 | a | 31.09 | 32.95 | u | ----- | z | ----- | z | 69.50 | o | 75.32 | 73.74 | 64.72 | a | 54.43 | h | 39.22 | 31.42 | 49.38 | e | |||||
| 1944 | 18.56 | e | 28.33 | 33.65 | a | 45.80 | 60.29 | 63.17 | a | 75.52 | 74.50 | 64.62 | 57.81 | 37.10 | 29.40 | a | 49.06 | |||||||||
| 1945 | 31.92 | 35.17 | a | 37.63 | 44.62 | a | 59.02 | c | 62.24 | a | 77.07 | d | 73.34 | c | 58.50 | a | 54.52 | e | 37.71 | i | 28.48 | g | 53.40 | b | ||
| 1946 | 27.19 | 29.93 | f | 42.94 | n | 53.90 | d | 57.04 | c | 69.19 | d | 75.91 | d | 75.26 | d | 62.48 | f | 45.14 | c | 38.02 | c | 35.96 | c | 53.07 | c | |
| 1947 | 19.62 | a | 36.55 | 43.47 | 47.77 | d | 60.95 | c | 64.65 | 82.78 | m | ----- | z | ----- | z | ----- | z | ----- | z | 26.13 | a | 42.73 | e | |||
| 1948 | 26.95 | 30.90 | 34.81 | e | 47.59 | b | 59.94 | 68.28 | 77.73 | a | 75.50 | 63.07 | a | 53.29 | 35.67 | 25.69 | 49.95 | |||||||||
| 1949 | 11.84 | 23.27 | 40.69 | 54.97 | 59.12 | a | 66.73 | 76.37 | 76.03 | 67.14 | a | 48.31 | 44.90 | 29.63 | 49.92 | |||||||||||
| 1950 | 25.42 | 35.41 | 39.97 | 47.18 | 54.58 | 64.72 | 73.45 | 71.66 | 62.60 | 57.24 | 42.03 | 33.63 | 50.66 | |||||||||||||
| 1951 | 27.84 | 32.70 | 36.18 | 51.58 | 58.85 | 64.65 | 76.60 | 70.98 | 64.12 | 50.61 | 37.28 | 27.55 | 49.91 | |||||||||||||
| 1952 | 26.13 | 26.90 | 32.32 | 51.23 | 60.31 | 67.52 | 74.98 | a | 73.85 | 68.45 | 57.48 | 34.71 | a | 31.65 | 50.46 | |||||||||||
| 1953 | 39.52 | 36.07 | 43.66 | 47.38 | a | 54.32 | 66.88 | 78.90 | 75.21 | 67.50 | 54.76 | 46.38 | 30.11 | 53.39 | ||||||||||||
| 1954 | 33.71 | 34.96 | 38.16 | 54.55 | 62.12 | a | 67.34 | a | 78.92 | 73.79 | 65.84 | a | 53.68 | 41.77 | 30.02 | 52.91 | ||||||||||
| 1955 | 19.37 | 24.57 | 34.53 | a | 46.28 | a | 58.63 | 66.08 | 75.02 | 76.08 | 64.47 | 53.84 | 35.85 | 36.39 | 49.26 | |||||||||||
| 1956 | 35.28 | a | 25.31 | 40.92 | a | 50.15 | 61.35 | a | 70.03 | 77.95 | 72.60 | 67.08 | 52.77 | 34.07 | 29.87 | 51.45 | ||||||||||
| 1957 | 24.52 | 38.91 | 43.06 | 48.05 | 58.48 | 67.88 | 76.19 | 76.50 | 64.42 | 51.93 | b | 34.57 | 33.03 | a | 51.46 | |||||||||||
| 1958 | 27.74 | 40.27 | 39.44 | 47.80 | 65.08 | 71.34 | a | 75.23 | a | 77.06 | 66.15 | 55.65 | 39.07 | 35.63 | 53.37 | |||||||||||
| 1959 | 33.05 | 35.59 | 41.27 | 51.92 | 56.24 | 72.35 | 77.26 | 74.21 | 61.90 | 51.94 | 39.33 | 30.32 | 52.11 | |||||||||||||
| 1960 | 24.24 | 28.72 | 42.53 | 50.79 | a | 57.98 | a | 70.85 | 80.29 | 73.18 | 68.67 | 52.77 | 41.50 | a | 31.53 | 51.92 | ||||||||||
| 1961 | 30.87 | 37.62 | 42.02 | 49.87 | 60.55 | 75.78 | 79.61 | 77.85 | 58.40 | 51.00 | 37.29 | a | 29.35 | 52.52 | ||||||||||||
| 1962 | 20.17 | b | 29.79 | b | 37.52 | a | 52.63 | 56.89 | 66.48 | 73.87 | 72.16 | 65.53 | a | 55.63 | 44.17 | 31.11 | 50.50 | |||||||||
| 1963 | 23.81 | 42.39 | 42.27 | 45.93 | 63.32 | 64.03 | a | 78.39 | 78.11 | 68.47 | 58.55 | 39.45 | 26.06 | 52.57 | ||||||||||||
| 1964 | 22.37 | 24.76 | 32.35 | a | 47.36 | a | 58.08 | 63.82 | 79.37 | 73.35 | 64.53 | 55.90 | 39.10 | a | 34.52 | 49.63 | ||||||||||
| 1965 | 32.37 | 34.77 | 40.39 | 51.67 | 57.45 | 66.63 | 77.22 | b | 72.60 | 57.82 | 55.85 | 45.30 | 29.48 | a | 51.80 | |||||||||||
| 1966 | 29.77 | 29.75 | 42.08 | 50.20 | 63.06 | 69.20 | 78.80 | c | 73.50 | 66.70 | 49.84 | 42.22 | 26.89 | 51.83 | ||||||||||||
| 1967 | 30.29 | 37.36 | 42.65 | 45.38 | 58.68 | 64.50 | 78.26 | 79.55 | 66.78 | 52.45 | 44.02 | 25.23 | 52.09 | |||||||||||||
| 1968 | 23.45 | 35.82 | a | 45.02 | 45.65 | 58.73 | 67.50 | 78.19 | 68.85 | 61.95 | 51.98 | a | 36.88 | 29.82 | 50.32 | |||||||||||
| 1969 | 30.82 | 30.09 | 35.42 | 50.72 | 65.76 | 65.12 | 77.00 | 77.53 | 69.12 | 47.13 | a | 39.43 | 32.19 | 51.69 | ||||||||||||
| 1970 | 32.32 | 39.57 | 40.23 | 44.32 | 60.13 | 69.50 | 76.10 | 77.45 | 61.22 | 47.15 | 41.88 | 28.05 | 51.49 | |||||||||||||
| 1971 | 30.53 | 33.64 | 39.92 | 50.57 | a | 57.50 | 68.27 | 79.42 | f | 79.03 | 58.88 | e | 47.89 | 37.78 | 24.66 | b | 48.06 | a | ||||||||
| 1972 | 28.48 | b | 35.47 | 47.47 | 48.22 | a | 62.55 | 72.10 | 77.82 | 76.44 | 61.25 | 52.47 | 38.22 | 21.37 | 51.82 | |||||||||||
| 1973 | 22.31 | 28.30 | a | 38.77 | 47.30 | 61.27 | i | 70.32 | k | ----- | z | ----- | z | ----- | z | 53.06 | ----- | z | 32.26 | 37.00 | f | |||||
| 1974 | 25.45 | 28.62 | 43.00 | h | ----- | z | 61.02 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 38.36 | i | |||
| Period of Record Statistics | ||||||||||||||||||||||||||
| MEAN | 26.29 | 31.97 | 39.81 | 49.30 | 59.11 | 67.45 | 76.42 | 74.01 | 63.71 | 52.19 | 39.29 | 29.69 | 50.81 | |||||||||||||
| S.D. | 5.59 | 5.45 | 3.98 | 3.35 | 3.22 | 3.14 | 1.86 | 2.37 | 3.05 | 3.23 | 3.44 | 4.46 | 1.54 | |||||||||||||
| SKEW | -0.28 | -0.46 | -0.52 | 0.24 | -0.10 | 0.50 | -0.11 | 0.14 | -0.09 | -0.20 | -0.09 | -0.57 | 0.18 | |||||||||||||
| MAX | 39.52 | 42.39 | 48.09 | 58.16 | 66.10 | 75.78 | 80.29 | 79.55 | 69.48 | 58.55 | 46.38 | 39.04 | 54.63 | |||||||||||||
| MIN | 11.84 | 16.20 | 28.95 | 42.45 | 52.29 | 62.24 | 71.89 | 68.85 | 57.82 | 45.14 | 31.60 | 18.38 | 47.95 | |||||||||||||
| YRS | 58 | 59 | 57 | 60 | 58 | 57 | 56 | 57 | 56 | 56 | 56 | 59 | 44 | |||||||||||||