| YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
| 1951 | 31.44 | n | 37.46 | a | 40.36 | f | 53.93 | h | 59.25 | c | 63.42 | e | 77.27 | e | 74.54 | d | 65.74 | g | 50.48 | g | 39.75 | l | 31.31 | r | 62.39 | |
| 1952 | 29.64 | j | 31.75 | g | 37.62 | k | 56.29 | w | 60.42 | f | 66.38 | i | 74.25 | g | 72.00 | t | 66.50 | o | 60.87 | p | 35.36 | s | 34.58 | r | 9999.00 | |
| 1953 | 41.77 | p | 38.65 | k | 45.35 | k | 48.36 | h | 52.85 | g | 60.31 | f | 75.96 | g | 73.02 | f | 68.98 | d | 58.07 | i | 48.71 | k | 31.54 | r | 68.98 | |
| 1954 | 36.28 | m | 41.06 | k | 39.88 | k | 51.50 | r | 62.53 | n | 63.92 | l | 73.38 | o | 68.53 | n | 67.41 | s | 51.93 | p | 42.77 | s | 31.00 | m | 9999.00 | |
| 1955 | 26.25 | m | 30.16 | i | 39.03 | l | 47.83 | l | 56.74 | n | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1956 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1957 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 69.68 | 76.45 | 74.48 | 69.35 | 52.66 | 38.62 | 35.69 | 59.56 | ||||||||
| 1958 | 31.68 | 43.00 | 42.08 | 48.93 | 67.11 | 68.43 | 75.81 | 78.18 | 65.23 | 58.35 | 41.65 | 38.05 | 54.88 | |||||||||||||
| 1959 | 36.50 | 37.30 | 42.21 | 52.08 | 53.40 | 69.00 | 76.90 | 70.73 | 62.57 | 54.45 | 41.28 | 34.02 | a | 52.54 | ||||||||||||
| 1960 | 28.06 | 34.19 | 44.40 | 52.37 | 57.53 | 70.35 | 81.65 | 70.74 | 68.48 | 55.29 | 42.87 | 33.82 | 53.31 | |||||||||||||
| 1961 | 35.63 | 41.57 | 45.27 | 50.80 | 60.94 | 75.68 | 79.44 | 80.90 | a | 61.03 | 52.35 | 39.70 | 31.71 | 54.59 | ||||||||||||
| 1962 | 22.95 | 33.61 | 40.53 | 55.88 | 57.28 | a | 68.32 | 74.65 | 73.35 | 68.22 | 54.81 | 44.13 | 36.76 | 52.54 | ||||||||||||
| 1963 | 26.58 | 44.20 | 44.40 | 48.42 | 61.98 | 64.82 | 73.08 | 74.92 | 72.78 | 60.60 | 44.29 | b | 30.66 | 53.89 | ||||||||||||
| 1964 | 29.02 | g | 28.09 | l | 37.36 | j | 46.83 | a | 55.16 | 63.77 | 76.65 | a | 71.26 | 61.30 | 57.00 | d | 40.05 | k | 34.98 | g | 61.71 | |||||
| 1965 | 33.03 | k | 36.64 | 39.10 | 51.03 | a | 55.50 | a | 65.62 | 75.37 | 72.90 | 58.72 | 58.95 | b | 48.32 | k | 33.88 | j | 57.09 | |||||||
| 1966 | 34.92 | k | 33.74 | i | 43.02 | j | 50.53 | 63.10 | 66.52 | 75.32 | 74.95 | a | 69.33 | 53.31 | d | 45.38 | j | 34.07 | j | 64.72 | ||||||
| 1967 | 35.45 | j | 38.61 | i | 43.56 | m | 44.41 | g | 57.03 | 65.57 | 78.79 | 79.89 | 71.32 | 53.62 | g | 43.67 | j | 29.34 | l | 70.52 | ||||||
| 1968 | 32.18 | i | 40.50 | i | 46.05 | l | 46.09 | a | 57.10 | 66.30 | 77.66 | 68.90 | 63.15 | 52.80 | d | 40.26 | k | 33.95 | k | 61.71 | ||||||
| 1969 | 32.30 | i | 35.39 | j | 40.12 | k | 51.00 | b | 61.53 | 66.45 | 74.29 | 74.44 | 66.62 | 48.17 | d | 43.47 | m | 35.52 | j | 63.21 | ||||||
| 1970 | 35.58 | l | 40.84 | i | 41.70 | a | 42.88 | 57.92 | 69.10 | 75.94 | 76.79 | 58.55 | 49.60 | a | 42.67 | 32.06 | 54.72 | |||||||||
| 1971 | 32.45 | 36.39 | 38.27 | 48.27 | 59.10 | 64.05 | 74.85 | 79.44 | 59.52 | 49.19 | 38.92 | 30.35 | 50.90 | |||||||||||||
| 1972 | 29.69 | 34.57 | 44.71 | 47.13 | 59.61 | 67.68 | 72.65 | 75.87 | 59.67 | 53.23 | 41.05 | 26.71 | 51.05 | |||||||||||||
| 1973 | 31.52 | 39.12 | 42.74 | 48.35 | 60.24 | 66.07 | 75.29 | 73.47 | 62.98 | 52.87 | 40.32 | 36.63 | 52.47 | |||||||||||||
| 1974 | 28.27 | 37.15 | d | 42.40 | 47.40 | 55.03 | 70.48 | 73.47 | 71.52 | 65.95 | 51.89 | 42.93 | 31.48 | 51.50 | ||||||||||||
| 1975 | 27.19 | 34.79 | 38.92 | 42.28 | 54.18 | 62.65 | 78.02 | 69.97 | 67.00 | 52.10 | 38.85 | 31.90 | 49.82 | |||||||||||||
| 1976 | 31.47 | 34.10 | 36.92 | 47.50 | 59.40 | 60.70 | b | 73.84 | 68.45 | 64.52 | 51.69 | 42.60 | 31.42 | 50.22 | ||||||||||||
| 1977 | 19.97 | 35.14 | 38.10 | b | 51.74 | c | 52.52 | 70.03 | 70.97 | 73.34 | 62.85 | 54.08 | 38.95 | 37.02 | 50.39 | |||||||||||
| 1978 | 36.61 | 37.30 | 47.73 | 50.52 | 55.34 | 64.92 | 73.50 | 70.52 | 61.45 | 54.10 | 36.58 | 27.32 | 51.32 | |||||||||||||
| 1979 | 17.98 | 35.04 | 44.05 | 48.98 | 57.85 | a | 66.62 | 74.57 | a | 73.10 | 67.60 | 55.15 | 37.06 | m | 36.58 | s | 54.09 | |||||||||
| 1980 | 29.38 | n | 43.25 | i | 40.68 | 52.85 | 58.02 | 63.58 | 74.21 | 68.97 | a | 63.38 | 53.89 | c | 41.73 | 35.12 | c | 55.24 | ||||||||
| 1981 | 35.02 | 37.89 | 45.55 | 49.82 | b | 55.60 | 63.68 | 72.11 | 76.98 | a | 65.41 | b | 49.84 | f | 45.62 | 36.77 | 53.13 | |||||||||
| 1982 | 26.69 | 30.07 | 42.37 | 46.20 | 55.15 | 67.00 | 69.32 | i | 74.50 | i | 62.60 | 51.53 | 37.58 | 32.76 | 45.20 | |||||||||||
| 1983 | 36.42 | 40.64 | 45.03 | 48.12 | a | 57.63 | 63.73 | 69.56 | 76.94 | 62.90 | 53.89 | m | 43.02 | 25.98 | 51.82 | |||||||||||
| 1984 | 25.69 | 31.34 | 42.55 | 47.50 | 56.90 | 63.35 | 75.23 | 76.65 | 61.75 | 49.53 | 39.72 | 24.77 | 49.58 | |||||||||||||
| 1985 | 22.23 | 27.02 | 37.89 | 52.83 | 60.61 | 68.50 | ----- | z | 69.58 | 56.95 | 48.74 | 28.37 | 15.18 | 44.35 | ||||||||||||
| 1986 | 31.37 | 41.96 | 50.23 | 49.63 | 59.90 | 71.95 | 70.56 | 77.06 | 58.33 | 54.23 | 42.75 | 30.55 | 53.21 | |||||||||||||
| 1987 | 29.21 | 40.04 | 44.52 | 56.85 | 61.39 | 69.40 | 70.81 | 70.15 | 66.05 | 57.11 | 43.57 | 33.94 | 53.58 | |||||||||||||
| 1988 | 26.82 | 38.50 | 42.16 | 53.20 | 57.92 | 69.22 | 74.00 | 71.29 | 60.88 | 58.89 | 39.25 | 25.71 | 51.49 | |||||||||||||
| 1989 | 21.98 | a | 20.54 | 40.39 | 52.93 | 57.50 | 68.17 | 75.06 | 70.37 | 63.77 | 52.69 | 38.98 | a | 30.47 | o | 51.13 | ||||||||||
| 1990 | 32.84 | o | 29.90 | m | 42.79 | 53.73 | o | 54.89 | 65.08 | 76.18 | i | 72.29 | 69.47 | 53.47 | p | 38.30 | o | 26.46 | q | 60.90 | ||||||
| 1991 | 23.59 | o | 40.00 | m | 39.21 | n | 45.66 | n | 52.60 | j | 60.25 | 72.77 | 75.68 | 65.80 | 52.09 | n | 38.54 | p | 33.93 | p | 68.63 | |||||
| 1992 | 33.13 | p | 42.58 | p | 47.00 | o | 54.07 | o | 64.77 | i | 69.05 | ----- | z | 72.76 | 61.12 | 55.58 | m | 34.12 | r | 30.28 | m | 67.64 | ||||
| 1993 | 24.07 | p | 25.87 | m | 40.39 | m | 46.86 | l | 61.60 | 60.45 | 62.81 | 68.13 | 63.43 | 53.94 | o | 36.96 | q | 33.12 | n | 63.28 | ||||||
| 1994 | 35.17 | p | 33.20 | m | 46.95 | l | 52.96 | q | 60.48 | 65.73 | 75.13 | 74.82 | 66.55 | 50.80 | p | 32.96 | p | 31.18 | n | 68.54 | ||||||
| 1995 | 36.17 | p | 40.60 | m | 42.92 | l | 49.38 | n | 57.26 | l | 63.53 | 72.63 | 69.71 | 65.25 | 50.03 | n | 43.82 | p | 34.17 | p | 67.78 | |||||
| 1996 | 32.59 | o | 36.37 | n | 44.26 | n | 51.09 | m | 54.94 | m | 66.12 | 75.34 | 72.52 | 59.55 | 53.47 | m | 41.61 | p | 34.96 | q | 68.38 | |||||
| 1997 | 29.82 | q | 35.37 | m | 45.37 | p | 49.17 | o | 61.85 | k | 66.03 | 71.84 | 74.11 | 67.40 | a | 53.19 | m | 46.29 | r | 30.94 | o | 69.85 | ||||
| 1998 | 37.13 | p | 40.25 | n | 41.94 | o | 51.28 | l | 56.11 | 61.75 | 77.85 | 74.79 | 70.14 | a | 51.21 | n | 41.25 | r | 30.26 | n | 68.13 | |||||
| 1999 | 32.33 | p | 33.70 | m | 42.67 | m | 45.60 | j | 54.76 | j | 64.13 | 70.53 | a | 73.34 | 61.26 | g | 53.58 | k | 45.29 | k | 31.42 | k | 69.34 | |||
| 2000 | 30.81 | m | 39.17 | i | 43.00 | h | 56.42 | j | 59.72 | h | 68.70 | e | 74.34 | c | 74.72 | a | 62.38 | 53.61 | i | 33.97 | m | 30.69 | o | 70.03 | ||
| 2001 | 29.47 | o | 32.50 | m | 46.79 | q | 50.50 | l | 61.64 | b | 66.94 | c | 74.76 | b | 77.75 | c | 69.90 | i | 55.46 | s | 42.38 | r | 31.66 | l | 70.27 | |
| 2002 | 31.16 | l | 33.11 | i | 40.72 | m | 50.47 | k | 58.59 | h | 69.14 | b | 80.73 | i | 71.29 | j | 67.17 | 51.21 | n | 42.85 | j | 38.93 | j | 68.15 | ||
| 2003 | 37.90 | j | 35.56 | l | 44.47 | k | 49.90 | j | 56.77 | g | 67.36 | e | 80.31 | 77.76 | 67.50 | 64.97 | k | 37.17 | l | 38.17 | m | 73.23 | ||||
| 2004 | 29.39 | l | 36.56 | k | 49.98 | i | 54.21 | i | 57.79 | e | 69.14 | b | 76.33 | e | 74.68 | 65.86 | p | 58.03 | o | 39.79 | k | 36.55 | j | 69.48 | ||
| 2005 | 33.24 | l | 37.21 | k | 46.23 | i | 50.07 | i | 57.08 | k | 63.60 | f | 76.48 | f | 76.18 | 63.73 | 55.98 | i | 40.11 | k | 27.91 | o | 69.96 | |||
| 2006 | 35.78 | o | 35.00 | k | 43.30 | k | 52.69 | n | 61.60 | f | 69.90 | a | 81.00 | h | 73.18 | 65.23 | 54.22 | o | 42.32 | m | 31.46 | r | 69.44 | |||
| 2007 | 29.32 | n | 39.47 | k | 47.50 | o | 49.79 | k | 62.40 | j | 72.35 | j | 82.52 | g | 75.47 | n | 67.67 | i | 53.83 | m | 44.95 | t | 33.22 | m | 9999.00 | |
| 2008 | 23.77 | p | 31.00 | u | 39.56 | o | 47.14 | p | 63.17 | s | 70.73 | q | 78.30 | k | 74.60 | f | ----- | z | ----- | z | 44.88 | 31.21 | 38.05 | |||
| 2009 | 34.70 | u | 37.50 | 41.79 | e | 50.43 | 59.97 | 66.80 | 75.53 | 73.13 | 69.82 | 47.65 | 41.78 | 26.50 | 53.72 | |||||||||||
| 2010 | 37.03 | 38.89 | 43.81 | 47.83 | 52.03 | 65.40 | 73.32 | 71.19 | 65.82 | 56.63 | 38.95 | 34.92 | 52.15 | |||||||||||||
| 2011 | 29.56 | 34.31 | a | 42.17 | j | 45.67 | o | 54.79 | g | 58.88 | q | 73.66 | 75.95 | 70.10 | 54.22 | a | 39.08 | 30.73 | 50.95 | |||||||
| 2012 | 34.00 | 36.52 | ----- | z | 52.70 | 56.05 | t | 64.98 | 77.76 | 75.98 | 67.38 | 52.45 | 44.40 | 35.07 | a | 54.12 | ||||||||||
| 2013 | 21.03 | 34.88 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 27.95 | |||
| Period of Record Statistics | ||||||||||||||||||||||||||
| MEAN | 29.06 | 36.18 | 42.44 | 49.70 | 58.13 | 66.52 | 74.64 | 73.76 | 64.75 | 53.54 | 40.81 | 31.49 | 52.08 | |||||||||||||
| S.D. | 5.47 | 4.68 | 2.98 | 3.18 | 3.08 | 3.04 | 3.11 | 3.08 | 3.75 | 3.16 | 3.29 | 4.82 | 1.57 | |||||||||||||
| SKEW | -0.27 | -1.19 | 0.28 | -0.09 | 0.34 | 0.19 | -0.88 | 0.14 | -0.04 | 0.20 | -1.64 | -1.31 | 0.13 | |||||||||||||
| MAX | 37.03 | 44.20 | 50.23 | 56.85 | 67.11 | 75.68 | 81.65 | 80.90 | 72.78 | 60.60 | 45.62 | 38.05 | 54.88 | |||||||||||||
| MIN | 17.98 | 20.54 | 36.92 | 42.28 | 52.03 | 60.25 | 62.81 | 68.13 | 56.95 | 47.65 | 28.37 | 15.18 | 49.58 | |||||||||||||
| NO YRS | 28 | 31 | 30 | 34 | 41 | 53 | 48 | 53 | 52 | 34 | 31 | 30 | 19 | |||||||||||||