YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
1923 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 95.83 | 97.58 | ----- | z | 83.33 | 73.87 | 64.40 | 51.06 | 77.68 | f | ||||||
1924 | 54.13 | 61.10 | 61.23 | 70.33 | 83.06 | 99.31 | d | 97.15 | d | 96.12 | e | 88.38 | d | 77.11 | c | 62.21 | b | 60.22 | d | 75.86 | ||||||
1925 | 64.29 | c | 74.58 | d | 74.07 | b | 79.97 | 89.39 | 95.50 | 99.26 | 91.19 | 88.37 | 72.42 | 61.10 | ----- | z | 80.92 | a | ||||||||
1926 | ----- | z | ----- | z | ----- | z | ----- | z | 70.84 | 89.86 | b | 91.93 | b | 81.35 | 74.20 | 64.48 | 48.00 | 39.81 | 70.06 | d | ||||||
1927 | 37.61 | ----- | z | 46.74 | 55.37 | 71.29 | ----- | z | 79.87 | 77.52 | 63.23 | 51.03 | 46.67 | 35.39 | 56.47 | b | ||||||||||
1928 | 37.21 | g | 46.17 | 49.10 | 54.43 | 66.83 | a | 77.23 | 82.81 | 78.65 | 75.50 | 62.16 | 42.97 | 34.81 | 60.97 | a | ||||||||||
1929 | 34.58 | g | 56.22 | s | 64.50 | e | 73.42 | d | 85.78 | d | 95.84 | e | 95.15 | d | 90.52 | d | 88.89 | c | 80.22 | d | 65.44 | e | 60.52 | d | 80.03 | b |
1930 | 52.11 | d | 67.17 | d | 67.19 | e | 80.73 | d | 82.30 | d | 93.20 | e | 89.44 | d | 90.92 | e | 81.57 | 63.80 | u | 57.26 | c | 55.73 | e | 74.33 | a | |
1931 | 55.73 | e | 58.87 | e | 70.38 | e | 73.96 | d | 85.20 | f | 94.81 | d | 95.42 | e | 89.08 | e | 86.68 | e | 81.96 | d | 67.15 | d | 51.77 | e | 75.07 | a |
1932 | 52.76 | f | 61.83 | e | 66.15 | d | 75.96 | d | 82.75 | g | 91.58 | d | 90.68 | f | 89.96 | d | 85.08 | e | 73.85 | e | 67.16 | e | 49.88 | e | 73.49 | c |
1933 | 49.08 | f | 56.35 | e | 70.92 | e | 72.88 | e | 82.46 | e | 91.19 | d | 95.00 | f | 92.26 | d | 89.40 | e | 77.15 | e | 69.16 | e | 63.80 | f | 77.98 | c |
1934 | 58.12 | e | 66.57 | e | 73.96 | d | 79.40 | e | 89.13 | a | 93.90 | a | 95.35 | 91.26 | 87.07 | b | 80.77 | 65.67 | 58.40 | a | 78.30 | |||||
1935 | 57.57 | a | 58.25 | 68.48 | 76.63 | 80.77 | a | 93.87 | 94.81 | 90.10 | 83.33 | 79.52 | 64.97 | 54.97 | 75.27 | |||||||||||
1936 | 57.23 | 60.04 | a | 66.84 | 78.67 | 88.20 | f | 95.43 | 93.94 | 93.35 | 85.63 | 77.16 | 61.27 | 58.16 | 75.25 | a | ||||||||||
1937 | 51.84 | 61.54 | 65.94 | 78.40 | 87.71 | 95.33 | 96.53 | a | 97.16 | 90.37 | 79.65 | 69.80 | 57.84 | 77.67 | ||||||||||||
1938 | 58.94 | 65.21 | 70.61 | 78.07 | a | 87.39 | 95.80 | 92.84 | 94.48 | 87.37 | 82.94 | 65.70 | 60.74 | 78.34 | ||||||||||||
1939 | 56.55 | 56.14 | 71.84 | 79.77 | 88.23 | 96.87 | 94.61 | 93.23 | 87.87 | 76.94 | 62.57 | 62.29 | 77.24 | |||||||||||||
1940 | 56.74 | 60.76 | 70.97 | a | 75.92 | d | 87.03 | 91.43 | 97.74 | 91.71 | 88.97 | 78.27 | a | 63.30 | 61.10 | 76.99 | ||||||||||
1941 | 56.48 | 62.57 | 65.81 | 72.03 | 86.29 | 92.87 | 94.68 | 90.68 | 85.73 | 75.35 | 66.50 | 59.00 | 75.67 | |||||||||||||
1942 | 60.03 | 60.96 | 68.48 | 78.20 | 88.65 | 97.60 | 97.71 | 91.00 | 87.87 | 83.27 | t | 72.88 | d | 61.19 | 78.60 | a | ||||||||||
1943 | 57.77 | 68.00 | 71.42 | 84.77 | 90.19 | 94.40 | 94.71 | 91.84 | 88.87 | 77.65 | 68.77 | 56.84 | 78.77 | |||||||||||||
1944 | 57.16 | 62.59 | 67.13 | 75.60 | 86.29 | 95.87 | 95.10 | 94.19 | 86.37 | 78.77 | 62.70 | 58.61 | 76.70 | |||||||||||||
1945 | 59.03 | 66.50 | 68.06 | 77.13 | 88.52 | 95.03 | 99.97 | ----- | z | 91.83 | a | 77.84 | 68.93 | 58.23 | 77.37 | a | ||||||||||
1946 | 52.73 | a | 64.15 | a | 70.90 | a | 82.03 | 87.93 | a | 98.20 | 96.55 | 91.93 | a | 89.70 | 82.71 | ----- | z | ----- | z | 81.68 | b | |||||
1947 | ----- | z | 69.88 | k | 72.47 | a | 80.36 | e | ----- | z | ----- | z | 98.25 | c | 95.07 | a | 91.33 | 79.67 | j | ----- | z | 58.62 | g | 87.50 | g | |
1948 | 59.12 | g | ----- | z | ----- | z | 87.12 | f | 94.46 | g | 99.62 | d | 99.48 | d | 96.52 | f | 92.72 | e | 81.80 | f | 67.21 | f | ----- | z | 97.27 | i |
1949 | 53.13 | h | 64.64 | f | 73.08 | f | 82.12 | e | 90.08 | f | 96.31 | d | 96.28 | f | 94.85 | d | 91.62 | i | 78.81 | j | 75.86 | i | 61.62 | j | 91.09 | i |
1950 | 63.88 | o | 70.95 | i | 76.13 | h | 85.55 | j | 90.68 | i | 98.29 | i | 92.00 | k | 94.83 | h | 90.15 | j | 88.14 | i | 75.30 | j | 66.95 | k | ----- | z |
1951 | 62.18 | i | 64.26 | i | 71.36 | i | 78.80 | j | 87.59 | i | 98.12 | v | 98.68 | i | 93.74 | h | 95.32 | k | 83.04 | h | 68.19 | i | 60.10 | k | ----- | z |
1952 | 64.77 | i | 62.95 | i | 65.33 | j | 79.00 | h | 89.52 | j | 95.62 | i | 96.86 | i | 95.90 | j | 92.60 | j | 84.96 | h | 65.16 | k | 55.73 | i | ----- | z |
1953 | 64.52 | j | 62.85 | h | 71.09 | i | 77.91 | h | 84.52 | j | 98.52 | e | 96.00 | i | 96.00 | l | 93.14 | i | 81.50 | i | 71.75 | j | 57.14 | i | 98.52 | k |
1954 | 62.40 | k | 70.22 | j | 69.14 | i | 84.32 | h | 89.19 | j | 95.82 | h | 96.09 | h | 88.48 | j | 91.81 | i | 84.81 | j | 72.71 | i | 63.70 | h | ----- | z |
1955 | 56.33 | j | 63.56 | j | 72.00 | e | 79.17 | a | 83.44 | d | 96.07 | b | 92.52 | b | 90.65 | 91.62 | a | 82.97 | 68.96 | b | 64.55 | 82.20 | b | |||
1956 | 63.97 | 60.25 | a | 75.13 | 77.17 | a | 91.83 | a | 97.83 | 94.57 | c | 92.57 | c | 93.79 | a | 82.15 | d | 65.11 | c | 58.62 | b | 79.42 | ||||
1957 | 60.17 | a | 72.00 | d | 72.67 | j | 80.10 | i | ----- | z | 100.62 | v | 95.32 | 88.23 | 87.48 | a | 72.53 | a | 62.14 | b | 63.44 | f | 76.84 | e | ||
1958 | 57.60 | a | 63.67 | a | 61.55 | 77.43 | b | 88.80 | a | 97.33 | 96.83 | h | 91.31 | b | 84.11 | c | 72.58 | 66.58 | f | 73.23 | a | 76.76 | b | |||
1959 | 66.97 | 66.60 | w | 71.37 | a | 79.93 | b | 87.54 | c | 96.85 | c | 95.33 | a | 87.62 | b | 88.79 | b | 79.96 | c | 63.57 | b | 56.97 | b | 79.54 | a | |
1960 | 52.87 | a | 60.52 | d | 75.20 | a | 80.72 | a | 86.33 | a | 99.67 | f | 104.20 | k | ----- | z | 96.05 | j | 77.67 | j | 71.38 | i | 56.23 | i | 71.13 | g |
1961 | 56.86 | i | 65.84 | i | 73.74 | h | 82.70 | j | 91.50 | i | 97.45 | h | 97.35 | k | 91.83 | h | 86.21 | k | 81.05 | i | 60.67 | i | 58.76 | f | ----- | z |
1962 | 53.48 | 66.25 | 64.16 | 81.47 | 85.42 | 93.17 | 90.61 | 96.10 | 87.33 | 79.77 | 70.23 | 57.19 | 77.10 | |||||||||||||
1963 | 55.77 | 63.93 | 71.23 | 79.27 | 89.45 | 94.00 | 95.94 | 86.94 | 86.63 | 80.45 | 66.80 | 59.03 | 77.45 | |||||||||||||
1964 | 56.55 | 58.86 | 66.45 | 75.30 | 86.52 | 92.97 | 95.65 | 91.39 | 83.17 | 79.19 | 66.23 | 58.77 | 75.92 | |||||||||||||
1965 | 61.00 | 61.11 | 66.71 | 78.17 | 84.00 | 91.40 | 94.16 | 91.81 | 83.87 | 80.42 | 71.40 | 56.29 | 76.69 | |||||||||||||
1966 | 53.29 | 55.43 | 71.00 | 78.43 | 88.52 | 93.93 | 97.35 | 90.87 | 85.27 | 77.90 | 71.27 | 58.39 | 76.80 | |||||||||||||
1967 | 61.35 | 66.46 | 75.42 | 79.03 | 85.35 | 92.33 | 94.13 | 90.81 | 84.80 | 79.90 | 68.50 | 51.39 | 77.46 | |||||||||||||
1968 | 54.97 | 63.93 | 64.97 | 73.17 | 86.65 | 96.37 | 91.55 | 89.35 | 88.27 | 83.35 | 65.53 | 57.94 | 76.34 | |||||||||||||
1969 | 63.81 | 61.96 | 67.42 | 81.90 | 87.83 | b | 96.41 | h | 95.36 | c | 97.75 | c | 88.74 | g | 75.18 | i | 62.46 | d | 58.73 | a | 75.25 | c | ||||
1970 | 59.82 | c | 64.75 | l | 66.52 | b | 75.93 | c | 88.18 | i | 94.74 | c | 96.16 | 92.32 | 87.00 | c | 74.75 | o | 69.75 | j | 62.44 | d | 79.37 | d | ||
1971 | 60.90 | 62.00 | n | 75.92 | e | 75.50 | l | 85.63 | l | 95.12 | d | 97.95 | j | 90.70 | u | ----- | z | ----- | z | 63.95 | k | 54.11 | d | 71.51 | h | |
1972 | 60.53 | n | 66.72 | 77.17 | b | 82.73 | d | 86.87 | 94.92 | d | 95.76 | j | 88.08 | g | 84.60 | t | 76.55 | 61.40 | j | 59.67 | g | 80.83 | f | |||
1973 | 54.00 | b | 58.61 | e | 62.97 | b | 70.52 | i | 85.88 | e | 95.36 | b | 96.93 | c | 93.50 | a | 93.68 | k | 81.87 | 71.39 | b | 61.22 | d | 76.17 | b | |
1974 | 59.77 | 64.82 | 74.23 | 80.37 | 89.88 | f | 99.97 | 92.52 | 91.14 | i | 75.92 | r | 74.13 | 65.15 | c | 54.67 | a | 73.96 | c | |||||||
1975 | 58.74 | 61.04 | 68.00 | 73.37 | 82.77 | i | 94.77 | 93.00 | r | 94.13 | 82.53 | 78.52 | 66.93 | 58.55 | 73.66 | b | ||||||||||
1976 | 56.61 | 67.34 | 69.68 | 74.85 | c | ----- | z | 94.30 | j | 90.35 | 90.10 | 80.63 | 69.77 | a | 59.62 | i | 55.39 | 72.75 | c | |||||||
1977 | 53.58 | 62.96 | 64.55 | 75.87 | 83.90 | 94.43 | 92.87 | 92.81 | 88.97 | 77.06 | 66.90 | 62.19 | 76.34 | |||||||||||||
1978 | 57.42 | 58.79 | 69.81 | 78.87 | 86.13 | 97.33 | 97.77 | 91.81 | 84.73 | 77.94 | 64.57 | 51.45 | 76.38 | |||||||||||||
1979 | 50.80 | a | 61.36 | 66.97 | 78.23 | 82.26 | 91.40 | 95.68 | 90.03 | a | 87.75 | b | 83.19 | 62.53 | 58.06 | 75.69 | ||||||||||
1980 | 59.10 | 61.66 | 66.61 | 75.53 | 83.45 | 99.23 | 97.77 | 90.55 | 87.97 | 75.90 | a | 65.30 | 64.19 | 77.27 | ||||||||||||
1981 | 56.32 | 65.57 | 64.61 | 77.67 | 83.94 | 95.48 | a | 91.58 | 90.55 | 87.13 | 76.45 | 69.97 | 63.23 | 76.87 | ||||||||||||
1982 | 59.68 | 62.92 | b | 69.57 | a | 77.87 | 84.48 | 94.67 | 93.55 | 92.87 | 88.21 | a | 79.20 | a | 62.57 | 52.13 | 76.48 | |||||||||
1983 | 54.34 | b | 61.04 | 64.71 | 68.63 | 84.42 | 92.63 | 93.94 | 92.26 | 87.63 | 74.84 | 63.90 | 58.35 | 74.72 | ||||||||||||
1984 | 56.71 | 62.21 | 70.77 | 75.53 | 90.74 | 92.23 | 93.19 | 87.19 | 87.07 | 70.77 | 63.67 | 56.16 | 75.52 | |||||||||||||
1985 | 51.13 | 58.96 | 68.42 | 77.80 | 85.87 | 95.20 | 95.00 | 92.26 | 85.23 | 73.74 | 65.33 | 59.61 | 75.71 | |||||||||||||
1986 | 63.65 | 64.14 | 72.32 | 79.97 | 86.58 | 91.67 | 91.23 | i | 90.76 | f | 86.07 | 75.06 | 61.70 | 53.26 | 73.44 | b | ||||||||||
1987 | 57.23 | 60.18 | 66.10 | 76.77 | 82.81 | 94.83 | 95.58 | 89.48 | 85.27 | 82.39 | 66.70 | 55.93 | a | 76.10 | ||||||||||||
1988 | 57.29 | 65.21 | 70.81 | 76.90 | 86.58 | 95.00 | 93.84 | 86.81 | 86.77 | 81.87 | 69.93 | 57.29 | 77.36 | |||||||||||||
1989 | 58.32 | 66.25 | 76.68 | 85.80 | 90.84 | 97.40 | 96.87 | 91.42 | 90.07 | 79.81 | 69.03 | 58.16 | 80.05 | |||||||||||||
1990 | 58.97 | 61.32 | 70.13 | 81.10 | 86.55 | 101.03 | 91.42 | 87.29 | 86.70 | 78.55 | 66.03 | 55.65 | 77.06 | |||||||||||||
1991 | 56.42 | 64.61 | 65.87 | 77.60 | 86.29 | 93.27 | 92.32 | 89.55 | 84.40 | 81.84 | 65.17 | 55.16 | 76.04 | |||||||||||||
1992 | 51.42 | 61.59 | 68.45 | 79.33 | 81.97 | 94.87 | 94.42 | 91.58 | 91.70 | 83.29 | 63.70 | 55.77 | 76.51 | |||||||||||||
1993 | 58.00 | 62.00 | 71.29 | 80.57 | 88.68 | 97.80 | 95.61 | 91.94 | 90.43 | 79.06 | 66.93 | 59.87 | 78.52 | |||||||||||||
1994 | 61.84 | 64.32 | 71.47 | a | 79.57 | 87.97 | 100.03 | 98.19 | 97.03 | 90.13 | 79.35 | 65.83 | 57.61 | 79.45 | ||||||||||||
1995 | 57.61 | 66.43 | 69.58 | 77.66 | a | 84.74 | 94.83 | 97.23 | 96.35 | 89.47 | 83.61 | 72.67 | 61.74 | 79.33 | ||||||||||||
1996 | 64.52 | 68.10 | 71.63 | a | 81.43 | 93.10 | 97.73 | 95.48 | 91.45 | 84.70 | 79.61 | 68.23 | 62.29 | 79.86 | ||||||||||||
1997 | 56.55 | 63.79 | 73.55 | 75.83 | 89.90 | 95.37 | 96.16 | 93.58 | 91.87 | 79.13 | 67.60 | 53.47 | a | 78.07 | ||||||||||||
1998 | 61.77 | 59.39 | 67.73 | a | 74.00 | d | 86.80 | a | 95.32 | b | 93.20 | a | 94.13 | 91.48 | a | 78.67 | d | ----- | z | 59.45 | 78.36 | a | ||||
1999 | 64.58 | 69.14 | 74.80 | a | 76.00 | 87.06 | 93.14 | a | 89.68 | 94.00 | v | 89.00 | b | 81.68 | 73.50 | 56.53 | a | 77.74 | a | |||||||
2000 | 63.90 | 68.39 | a | 71.39 | 82.83 | 92.40 | a | 92.07 | b | 94.50 | a | 92.40 | a | 91.03 | 72.94 | 58.37 | 60.48 | 78.39 | ||||||||
2001 | 53.19 | 62.67 | a | 68.81 | 78.03 | 88.87 | 95.80 | 92.52 | b | 90.57 | a | 90.07 | 81.58 | 67.90 | 57.10 | 77.26 | ||||||||||
2002 | 59.03 | a | 61.11 | a | 69.87 | 82.73 | 88.16 | 97.29 | b | 93.58 | 92.97 | a | 87.87 | 75.68 | 66.37 | 54.06 | 77.39 | |||||||||
2003 | 63.21 | b | 60.79 | 67.16 | 77.38 | a | 88.42 | 94.60 | 99.23 | 94.06 | 90.50 | 82.42 | 67.38 | a | 61.57 | q | 80.47 | a | ||||||||
2004 | 56.15 | e | 58.55 | 71.32 | 73.43 | 87.29 | 94.00 | 94.23 | 89.10 | 85.17 | 77.62 | b | 60.85 | c | 55.97 | 75.31 | ||||||||||
2005 | 59.06 | 56.96 | a | 64.97 | a | 77.43 | 87.68 | 95.13 | 97.55 | 90.55 | 89.03 | 77.03 | 70.23 | 61.70 | a | 77.28 | ||||||||||
2006 | 61.80 | a | 66.32 | 68.48 | 81.37 | 88.66 | b | 94.86 | a | 93.33 | a | 84.63 | d | 80.67 | 74.52 | 69.53 | 57.26 | 76.79 | ||||||||
2007 | 49.68 | 56.78 | a | 69.74 | 76.75 | b | 86.06 | 95.77 | 90.93 | a | 89.00 | d | 87.45 | a | 79.83 | b | 69.69 | a | 55.60 | a | 75.61 | |||||
2008 | 56.06 | 64.96 | c | 70.68 | 77.70 | 84.60 | a | 96.37 | 88.84 | 87.32 | c | 84.04 | c | 78.73 | e | 66.82 | b | 58.97 | a | 76.26 | ||||||
2009 | 60.48 | 66.46 | 71.65 | 76.46 | d | 87.40 | a | 89.48 | c | 95.47 | a | 91.70 | d | 84.64 | e | 75.78 | d | 67.29 | b | 53.10 | 76.66 | |||||
2010 | 53.88 | e | 56.96 | b | 67.03 | 75.10 | a | 85.37 | a | 92.03 | 90.08 | e | 89.08 | e | 85.83 | f | 70.57 | c | 61.29 | b | 63.39 | 73.16 | a | |||
2011 | 57.58 | 62.11 | a | 75.40 | a | 80.85 | c | 84.93 | d | 98.61 | b | 95.13 | 92.86 | c | 88.57 | g | 79.76 | b | 64.00 | 51.17 | a | 76.58 | a | |||
2012 | 61.10 | 62.07 | a | 70.55 | 80.86 | a | 88.17 | b | 98.47 | 92.26 | 94.11 | c | 86.38 | a | 79.55 | i | 70.80 | 57.73 | e | 78.41 | a | |||||
2013 | 54.71 | g | 58.86 | g | 74.35 | n | 77.44 | l | 85.07 | p | 98.96 | g | 93.33 | p | 90.89 | l | 85.48 | e | 77.50 | k | 65.64 | e | 55.62 | g | 75.56 | j |
2014 | 62.12 | o | 68.67 | p | 68.75 | w | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 77.54 | c | 64.97 | 58.23 | 66.91 | i | ||
2015 | 55.13 | 66.81 | b | 69.71 | 75.77 | 81.28 | b | 95.47 | 90.10 | 92.61 | 86.38 | d | 77.93 | a | 65.50 | 57.00 | a | 76.14 | ||||||||
2016 | 55.45 | 67.97 | 73.87 | 76.38 | d | 83.68 | 95.18 | b | 96.61 | 87.57 | a | 86.07 | b | 83.34 | b | 67.43 | b | 58.93 | a | 77.71 | ||||||
2017 | 57.13 | 65.46 | 75.71 | 81.70 | c | 85.47 | a | 96.79 | a | 91.71 | 88.54 | c | 87.88 | e | 80.42 | 74.60 | 59.58 | 78.75 | ||||||||
2018 | 61.48 | 64.14 | 71.20 | a | 82.38 | a | 89.60 | a | 96.53 | 92.77 | 91.94 | 88.27 | 71.39 | 64.30 | 55.29 | 77.44 | ||||||||||
2019 | 56.03 | 59.00 | 69.06 | 77.93 | 81.42 | 94.63 | 95.52 | 94.06 | 85.93 | 76.03 | 63.60 | 54.42 | 75.64 | |||||||||||||
2020 | 58.52 | 60.31 | 67.00 | 78.70 | 89.61 | 94.92 | r | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 70.83 | g | |||||
Period of Record Statistics | ||||||||||||||||||||||||||
MEAN | 57.49 | 62.68 | 69.06 | 77.46 | 85.96 | 95.01 | 94.31 | 91.10 | 86.72 | 77.50 | 65.48 | 57.02 | 77.08 | |||||||||||||
S.D. | 4.30 | 4.14 | 4.82 | 4.70 | 4.24 | 3.07 | 3.28 | 3.50 | 4.26 | 5.08 | 5.17 | 5.47 | 1.26 | |||||||||||||
SKEW | -1.05 | -0.43 | -1.87 | -2.60 | -2.20 | -2.21 | -1.55 | -1.37 | -2.50 | -2.33 | -1.96 | -1.63 | 0.54 | |||||||||||||
MAX | 66.97 | 74.58 | 77.17 | 85.80 | 93.10 | 101.03 | 99.97 | 97.75 | 93.79 | 83.61 | 74.60 | 73.23 | 80.05 | |||||||||||||
MIN | 37.61 | 46.17 | 46.74 | 54.43 | 66.83 | 77.23 | 79.87 | 77.52 | 63.23 | 51.03 | 42.97 | 34.81 | 74.72 | |||||||||||||
YRS | 79 | 79 | 85 | 84 | 77 | 84 | 80 | 80 | 81 | 80 | 80 | 80 | 52 |