| YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
| 1937 | 18.38 | b | 37.39 | 41.84 | 46.67 | 72.16 | 74.00 | 85.67 | a | 84.52 | 76.87 | 65.63 | a | 50.50 | 42.52 | 58.01 | ||||||||||
| 1938 | 39.29 | 37.14 | 41.32 | 56.07 | 65.16 | 75.47 | 85.26 | 82.42 | 76.97 | 59.10 | 42.30 | 41.26 | 58.48 | |||||||||||||
| 1939 | 39.16 | 36.11 | 51.13 | 64.60 | 69.74 | 70.87 | 86.94 | 86.90 | 76.13 | 63.55 | 54.23 | 44.00 | 61.95 | |||||||||||||
| 1940 | 36.58 | 39.62 | 51.42 | 57.67 | 72.23 | 82.52 | a | 84.90 | 88.13 | 70.80 | 61.55 | 39.47 | 40.58 | 60.45 | ||||||||||||
| 1941 | 36.81 | 39.75 | 52.13 | 56.62 | a | 65.13 | 70.07 | 84.90 | 78.29 | 66.60 | 58.84 | 47.83 | 36.55 | 57.79 | ||||||||||||
| 1942 | 28.06 | 34.57 | 43.65 | 57.77 | 58.60 | a | 68.57 | 86.03 | 85.81 | 76.40 | 64.06 | 42.77 | 36.26 | 56.88 | ||||||||||||
| 1943 | 32.06 | 39.15 | a | 45.97 | 60.30 | 62.06 | 66.13 | 83.52 | 80.06 | 81.20 | 59.57 | a | 45.63 | 37.73 | a | 57.78 | ||||||||||
| 1944 | 30.00 | 36.38 | 45.94 | 53.73 | 64.84 | 66.33 | 79.61 | 79.61 | 74.83 | 66.19 | 38.10 | 34.61 | 55.85 | |||||||||||||
| 1945 | 36.87 | 41.04 | 43.77 | 54.63 | 62.10 | 69.83 | a | 86.68 | 84.06 | 73.13 | 64.42 | 42.07 | 33.97 | 57.71 | ||||||||||||
| 1946 | 33.90 | 37.11 | 45.45 | 60.20 | 65.23 | 70.33 | 83.33 | a | 84.32 | 70.90 | 51.55 | 44.53 | 42.97 | 57.49 | ||||||||||||
| 1947 | 37.32 | 46.54 | 53.81 | 60.10 | 75.45 | 71.83 | 88.52 | 83.13 | 75.53 | 63.39 | 42.33 | 38.13 | 61.34 | |||||||||||||
| 1948 | 41.69 | b | 39.24 | 43.42 | 52.50 | 62.55 | 74.60 | 82.27 | a | 80.39 | 71.13 | 61.52 | 43.10 | 32.10 | 57.04 | |||||||||||
| 1949 | 25.81 | 35.82 | 43.68 | 63.83 | 68.83 | b | 78.31 | n | 85.17 | b | 83.63 | a | 78.45 | a | 56.54 | c | 56.50 | 36.23 | e | 57.68 | ||||||
| 1950 | 30.42 | 39.44 | a | 44.93 | a | 59.07 | c | 64.73 | a | 71.93 | 84.77 | 84.07 | c | 74.15 | c | 65.08 | e | 47.97 | a | 40.57 | a | 58.93 | ||||
| 1951 | 33.29 | 39.96 | a | 43.16 | 62.00 | a | 65.77 | a | 74.85 | d | 86.59 | d | 83.52 | 79.48 | a | 56.65 | 43.77 | 33.43 | a | 58.54 | ||||||
| 1952 | 33.27 | a | 37.79 | 39.90 | a | 63.70 | g | 66.58 | 70.90 | a | 85.48 | 84.58 | 79.43 | 71.97 | 48.83 | a | 38.33 | a | 59.73 | |||||||
| 1953 | 46.80 | a | 47.82 | 49.71 | 55.00 | 58.16 | 66.57 | 86.52 | 81.29 | 83.24 | e | 67.21 | g | 52.97 | 42.58 | 60.97 | ||||||||||
| 1954 | 39.97 | a | 47.42 | b | 46.81 | 60.13 | 71.03 | a | 68.97 | 86.39 | 78.93 | a | 74.31 | a | 64.43 | c | 55.80 | 37.97 | a | 61.01 | ||||||
| 1955 | 35.00 | 40.12 | b | 48.57 | a | 47.07 | 62.33 | a | 78.10 | 80.13 | a | 89.00 | b | 76.45 | a | 65.14 | b | 45.34 | a | 40.81 | 59.00 | |||||
| 1956 | 38.97 | 36.66 | 49.55 | b | 63.10 | 65.34 | b | 69.03 | 85.00 | a | 81.48 | d | 75.90 | 63.67 | a | 53.30 | c | 40.70 | a | 60.22 | ||||||
| 1957 | 30.35 | 44.08 | b | 48.67 | a | 57.70 | 64.58 | 75.87 | 82.00 | 79.19 | 78.64 | b | 53.82 | c | 44.31 | a | 39.90 | 58.26 | ||||||||
| 1958 | 34.45 | 43.36 | 41.50 | a | 51.97 | 71.97 | 72.14 | a | 82.71 | 85.52 | 71.43 | 67.23 | 48.37 | c | 44.00 | 59.55 | ||||||||||
| 1959 | 39.65 | 40.07 | a | 50.00 | 62.48 | a | 61.23 | 77.33 | 88.29 | 81.97 | 68.83 | a | 62.84 | 54.80 | 37.81 | e | 60.44 | |||||||||
| 1960 | 33.58 | g | 35.50 | a | 50.70 | a | 55.97 | 60.32 | 78.23 | 89.77 | 80.19 | 78.83 | 63.66 | b | 44.47 | 38.72 | b | 61.49 | ||||||||
| 1961 | 40.84 | 45.04 | a | 47.60 | a | 58.08 | d | 61.23 | 82.87 | 88.29 | 88.16 | 69.57 | 63.47 | a | 46.60 | 36.33 | a | 60.67 | ||||||||
| 1962 | 32.07 | a | 37.46 | 40.74 | d | 63.33 | c | 59.84 | 75.63 | 83.03 | 81.36 | f | 77.29 | f | 61.39 | 48.66 | a | 41.31 | b | 54.35 | ||||||
| 1963 | 38.00 | a | 50.67 | a | 48.42 | 49.50 | 65.48 | 71.27 | 79.52 | 83.29 | 78.60 | 63.84 | 46.73 | h | 40.00 | a | 60.78 | |||||||||
| 1964 | 36.13 | a | 41.64 | a | 43.30 | a | 55.67 | 63.83 | b | 69.79 | b | 83.37 | d | 82.31 | b | 74.10 | a | 69.13 | a | 44.65 | d | 36.76 | b | 58.39 | ||
| 1965 | 36.00 | 45.04 | 48.80 | a | 56.83 | 64.29 | c | 73.36 | b | 83.13 | a | 78.57 | c | 69.93 | a | 69.46 | c | 48.13 | 36.04 | e | 59.13 | |||||
| 1966 | 36.70 | a | 38.41 | a | 53.25 | g | 61.63 | c | 73.00 | c | 71.33 | o | 80.94 | 83.68 | 75.07 | a | 63.13 | a | 46.59 | a | 35.48 | b | 59.46 | |||
| 1967 | 38.60 | a | 44.50 | f | 42.81 | 45.45 | a | 64.65 | 74.03 | a | 86.94 | 89.03 | a | 78.61 | b | 60.63 | d | 53.48 | i | 35.86 | c | 61.66 | ||||
| 1968 | 36.33 | a | 47.07 | 52.61 | 53.37 | 62.97 | 74.48 | a | 87.42 | 73.68 | 71.93 | 58.68 | 41.67 | 34.50 | a | 57.89 | ||||||||||
| 1969 | 33.39 | 35.75 | 43.76 | j | 55.93 | 67.94 | 71.60 | 82.52 | 84.23 | 75.50 | 53.71 | 50.10 | 39.73 | a | 59.13 | |||||||||||
| 1970 | 37.06 | 46.33 | a | 46.45 | 48.60 | 65.32 | 75.33 | 85.71 | 87.61 | 68.73 | 58.10 | 45.23 | 35.56 | d | 58.34 | |||||||||||
| 1971 | 39.33 | g | 43.82 | 42.97 | a | 53.48 | a | 63.48 | 67.20 | 83.68 | 88.97 | 69.13 | 55.81 | 44.60 | 33.38 | b | 58.77 | |||||||||
| 1972 | 34.00 | a | 40.28 | 51.35 | 52.77 | 68.03 | 77.46 | b | 83.13 | a | 83.42 | 68.00 | b | 60.65 | 41.90 | 29.39 | 57.53 | |||||||||
| 1973 | 33.19 | 40.11 | a | 44.42 | 55.37 | 68.93 | a | 76.17 | a | 85.55 | 83.93 | a | 71.63 | 59.13 | 40.40 | 38.58 | 58.12 | |||||||||
| 1974 | 31.94 | 40.82 | 44.13 | 51.53 | 61.26 | 80.47 | 81.74 | 82.06 | 79.30 | 62.94 | 46.83 | 37.52 | b | 58.38 | ||||||||||||
| 1975 | 37.26 | d | 38.70 | h | 46.31 | r | 46.35 | d | 64.30 | d | 73.07 | 85.08 | f | 78.53 | a | 79.70 | 56.55 | 45.43 | 44.68 | i | 60.15 | |||||
| 1976 | 40.08 | e | 40.54 | e | 45.00 | 52.97 | a | 68.28 | b | 69.63 | 82.68 | 71.84 | 73.77 | 63.10 | b | 54.45 | a | 44.84 | 58.93 | |||||||
| 1977 | 32.32 | 45.64 | 43.77 | 60.87 | 54.23 | 78.10 | 81.32 | 84.03 | 68.97 | 61.84 | 43.48 | a | 38.39 | 57.75 | ||||||||||||
| 1978 | 36.77 | 40.14 | 51.90 | ----- | z | 58.65 | 73.03 | 83.06 | 80.03 | 68.55 | a | 67.81 | 43.60 | 33.13 | 57.88 | |||||||||||
| 1979 | 28.10 | a | 37.46 | b | 51.21 | g | 53.13 | 65.90 | 75.73 | 84.61 | 79.87 | 77.23 | 63.65 | 41.20 | 38.61 | 58.68 | ||||||||||
| 1980 | 35.10 | 43.03 | 44.42 | 56.80 | 61.87 | 67.00 | a | 81.42 | 79.48 | 72.63 | 60.07 | a | 45.65 | d | 41.42 | e | 57.41 | |||||||||
| 1981 | 38.00 | l | 39.79 | 47.03 | 53.93 | b | 59.31 | b | 71.10 | 79.40 | a | 88.16 | 74.37 | 55.25 | c | 47.19 | d | 37.00 | k | 61.55 | ||||||
| 1982 | 36.17 | y | ----- | z | 49.43 | x | 51.64 | p | 61.71 | n | 72.57 | 78.29 | 83.35 | 68.10 | 55.68 | 43.11 | k | 34.82 | t | 71.60 | ||||||
| 1983 | 43.15 | r | 42.50 | r | 46.07 | p | 51.25 | v | 65.42 | 70.21 | a | 75.58 | 82.10 | a | 72.27 | 62.58 | l | 44.81 | n | 34.18 | n | 73.11 | ||||
| 1984 | 34.12 | n | 39.83 | q | 48.00 | s | 48.57 | p | 59.17 | s | 67.82 | m | 87.20 | k | 86.38 | o | 73.78 | u | 63.50 | z | 41.62 | q | 30.90 | 30.90 | ||
| 1985 | 29.35 | 35.82 | 41.68 | 60.83 | 66.45 | 76.07 | o | 88.74 | 79.55 | 63.64 | p | 62.36 | q | 31.50 | n | 28.86 | j | 57.49 | ||||||||
| 1986 | 37.42 | 43.39 | 52.43 | a | 54.43 | 63.52 | 80.23 | 78.32 | 87.90 | 62.50 | 62.55 | 47.13 | 34.84 | 58.72 | ||||||||||||
| 1987 | 33.39 | 40.68 | 46.13 | 64.67 | 67.71 | 77.67 | 77.39 | 82.29 | 79.00 | 70.45 | 41.86 | i | 35.42 | 61.34 | ||||||||||||
| 1988 | 32.77 | 45.17 | 49.19 | 57.80 | 64.06 | 73.73 | 86.23 | 83.84 | 73.90 | 72.48 | 42.77 | 35.19 | 59.76 | |||||||||||||
| 1989 | 33.26 | 29.41 | a | 45.81 | 59.27 | 61.55 | 76.60 | 84.81 | 77.13 | 72.57 | 60.13 | 49.93 | 42.84 | 57.77 | ||||||||||||
| 1990 | 40.39 | 40.54 | 50.23 | 64.40 | 61.23 | 73.30 | 86.10 | 82.29 | 79.77 | 59.84 | 46.93 | ----- | z | 62.27 | ||||||||||||
| 1991 | 39.94 | 50.21 | 45.19 | 52.73 | 58.35 | 67.13 | 85.19 | 85.10 | 79.00 | 64.58 | 43.30 | 39.58 | 59.19 | |||||||||||||
| 1992 | 37.74 | 46.69 | 55.26 | 60.60 | 74.94 | 78.43 | 79.32 | 85.06 | 73.87 | 64.16 | 40.30 | 32.61 | 60.75 | |||||||||||||
| 1993 | 28.16 | 30.11 | 45.00 | 51.93 | 66.94 | 67.83 | 73.39 | 78.13 | a | 76.40 | 64.16 | 43.30 | ----- | z | 56.85 | |||||||||||
| 1994 | ----- | z | 39.61 | 54.81 | 57.77 | 66.65 | 74.60 | 87.94 | 85.90 | 77.63 | 59.10 | 36.03 | 36.61 | 61.51 | ||||||||||||
| 1995 | 36.52 | 50.64 | 46.13 | 51.97 | 61.74 | 69.07 | 82.26 | 79.61 | 77.27 | 60.35 | 51.83 | 35.39 | 58.56 | |||||||||||||
| 1996 | 37.26 | 39.24 | 48.55 | 55.50 | 59.58 | ----- | z | 86.16 | 85.19 | 69.23 | 59.16 | 45.57 | 38.32 | 56.71 | ||||||||||||
| 1997 | 34.63 | a | 37.07 | 47.84 | 51.30 | 69.71 | 71.50 | 81.35 | 83.61 | 71.93 | 56.06 | 41.27 | 32.73 | a | 56.58 | |||||||||||
| 1998 | 37.42 | 35.54 | 41.74 | 51.70 | 56.06 | 68.60 | 86.77 | 85.61 | 78.30 | 58.39 | ----- | z | 38.58 | 58.07 | ||||||||||||
| 1999 | 42.32 | 38.04 | 44.45 | ----- | z | 62.84 | 73.13 | 82.55 | 81.52 | 69.33 | 66.23 | 53.37 | 39.45 | 59.38 | ||||||||||||
| 2000 | 37.68 | l | 36.83 | 48.30 | a | 61.00 | 64.16 | 77.40 | 85.90 | k | ----- | z | 73.00 | i | 61.52 | 38.27 | o | 39.21 | l | 58.20 | ||||||
| 2001 | 33.81 | j | 36.53 | i | 48.18 | n | 55.59 | m | 76.06 | 73.28 | l | 89.53 | l | 92.11 | l | 80.20 | 67.45 | 48.43 | 34.23 | 61.28 | ||||||
| 2002 | 37.42 | 40.93 | 48.14 | i | 59.07 | 64.57 | a | 76.60 | 92.55 | 85.94 | n | 79.07 | 61.81 | 54.13 | 43.58 | 60.97 | ||||||||||
| 2003 | 45.06 | 45.86 | 54.23 | 51.73 | 68.65 | 80.67 | 92.13 | h | 87.00 | j | 75.53 | m | 66.35 | 42.88 | f | 38.00 | e | 56.32 | ||||||||
| 2004 | 33.87 | 37.48 | f | 54.88 | g | 59.10 | 63.52 | j | 75.25 | f | 87.70 | h | 84.52 | h | 73.90 | j | 60.62 | g | 46.59 | h | 41.27 | i | 46.49 | |||
| 2005 | 35.38 | e | 42.29 | 51.20 | f | 54.68 | h | 63.27 | i | 69.14 | h | 88.95 | l | 84.95 | k | 75.50 | j | 61.86 | i | 44.00 | h | 33.65 | k | 38.84 | ||
| 2006 | 38.79 | l | 40.39 | j | 43.27 | i | 45.56 | l | 60.81 | o | 75.80 | j | 86.74 | l | 82.45 | i | 68.47 | o | 60.85 | k | 46.56 | l | 37.72 | m | 9999.00 | |
| 2007 | 35.53 | l | 42.65 | h | 53.30 | k | 58.33 | o | 65.81 | o | 72.05 | k | 88.67 | s | 83.59 | n | 63.47 | m | 55.00 | l | 47.75 | n | 42.22 | m | 9999.00 | |
| 2008 | 33.45 | i | 43.36 | g | 43.90 | j | 51.10 | i | 63.32 | l | 74.37 | k | 86.10 | j | 82.29 | j | 76.86 | h | 65.18 | i | 50.19 | n | 39.68 | i | 9999.00 | |
| 2009 | 41.80 | k | 40.60 | h | 45.29 | j | 56.16 | k | 64.80 | k | 73.00 | j | 85.86 | i | 85.00 | l | 76.38 | i | 53.52 | j | 46.90 | i | 34.62 | j | 9999.00 | |
| 2010 | 38.61 | m | 40.11 | j | 48.73 | i | 51.65 | j | 56.30 | k | 70.37 | k | 84.39 | m | 78.91 | i | 75.33 | i | 61.65 | 41.83 | 34.39 | 45.96 | ||||
| 2011 | 36.06 | 39.21 | 42.39 | 48.86 | a | 55.03 | 67.13 | 80.48 | 85.45 | 79.70 | 61.34 | b | ----- | z | 41.35 | 57.91 | ||||||||||
| 2012 | 41.23 | a | 41.86 | 47.23 | a | 56.53 | 63.90 | 71.30 | 86.03 | 87.82 | c | 79.83 | 63.03 | 46.67 | 36.29 | 60.15 | ||||||||||
| 2013 | 28.29 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 28.29 | ||
| Period of Record Statistics | ||||||||||||||||||||||||||
| MEAN | 35.39 | 40.63 | 46.82 | 56.13 | 64.75 | 73.17 | 83.87 | 82.91 | 74.61 | 62.05 | 46.24 | 37.72 | 58.74 | |||||||||||||
| S.D. | 4.71 | 4.48 | 3.87 | 4.83 | 4.66 | 4.20 | 3.48 | 3.59 | 4.34 | 4.33 | 4.65 | 3.49 | 1.39 | |||||||||||||
| SKEW | -0.63 | 0.20 | 0.35 | -0.18 | 0.27 | 0.28 | -0.48 | -0.50 | -0.37 | 0.05 | 0.39 | 0.00 | 0.40 | |||||||||||||
| MAX | 46.80 | 50.67 | 55.26 | 64.67 | 76.06 | 82.87 | 92.55 | 89.03 | 83.24 | 72.48 | 56.50 | 44.84 | 61.95 | |||||||||||||
| MIN | 18.38 | 29.41 | 39.90 | 45.45 | 54.23 | 66.13 | 73.39 | 71.84 | 62.50 | 51.55 | 36.03 | 29.39 | 55.85 | |||||||||||||
| NO YRS | 63 | 64 | 60 | 63 | 67 | 63 | 64 | 63 | 64 | 66 | 59 | 62 | 39 | |||||||||||||