| YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
| 1963 | 33.58 | a | 47.50 | 44.61 | ----- | z | 55.98 | 59.52 | 62.27 | 64.89 | 64.35 | 53.42 | 46.29 | a | 39.27 | a | 51.97 | |||||||||
| 1964 | 41.32 | 40.69 | 43.69 | 47.43 | 52.37 | 58.93 | 64.50 | 62.61 | 57.73 | b | 53.37 | 41.60 | 38.81 | 50.26 | ||||||||||||
| 1965 | 39.85 | 42.15 | a | 47.16 | 50.77 | 52.55 | 58.83 | 67.06 | 66.53 | 60.02 | 54.69 | 47.92 | 38.48 | 52.17 | ||||||||||||
| 1966 | 39.45 | 41.46 | 44.84 | 51.70 | 56.23 | 61.05 | 64.05 | a | 65.11 | 62.60 | 52.02 | 47.48 | 44.13 | 52.51 | ||||||||||||
| 1967 | 43.27 | 42.29 | 43.35 | 45.28 | 55.06 | 63.55 | 67.44 | 70.94 | 64.68 | 52.50 | 46.08 | 40.65 | 52.92 | |||||||||||||
| 1968 | 39.58 | 47.84 | 47.15 | 47.30 | 55.03 | 60.05 | 66.03 | 65.24 | 60.27 | b | 51.15 | a | 45.77 | 39.06 | e | 52.04 | ||||||||||
| 1969 | 32.71 | 39.54 | c | 46.26 | 49.23 | 58.17 | b | 65.88 | b | 64.28 | a | 62.30 | d | 61.45 | a | 50.13 | 45.71 | b | 41.92 | a | 51.46 | |||||
| 1970 | 40.78 | a | 44.70 | 45.12 | a | 46.17 | 54.74 | 63.95 | 67.16 | 65.44 | 56.87 | 50.10 | 45.80 | 39.34 | 51.68 | |||||||||||
| 1971 | 39.13 | 40.95 | 42.12 | a | 47.48 | 54.58 | 57.00 | 66.35 | 68.41 | b | 58.07 | 49.24 | 43.37 | 38.65 | a | 50.45 | ||||||||||
| 1972 | 37.76 | 41.97 | 47.26 | 45.62 | 57.06 | 60.93 | 68.24 | 68.26 | 58.40 | 51.24 | 45.78 | 35.37 | 51.49 | |||||||||||||
| 1973 | 38.08 | 43.61 | 45.06 | e | 49.67 | 56.74 | 60.70 | 67.26 | 62.63 | 62.20 | 51.58 | 43.68 | 43.77 | 52.08 | ||||||||||||
| 1974 | 35.68 | c | 41.05 | 45.44 | 49.13 | 52.97 | 61.93 | a | 64.65 | 66.69 | 67.03 | 53.15 | 46.10 | 42.87 | 52.22 | |||||||||||
| 1975 | 42.11 | 41.00 | 43.66 | b | 45.67 | 54.61 | 60.05 | 67.10 | 63.10 | 64.18 | 52.24 | 44.36 | a | 42.24 | 51.69 | |||||||||||
| 1976 | 41.03 | 40.96 | a | 43.55 | 48.57 | 55.40 | 57.75 | 64.89 | 63.24 | 62.40 | a | 52.31 | b | 45.70 | 37.37 | 51.10 | ||||||||||
| 1977 | 36.87 | 43.61 | 42.87 | 51.40 | 51.98 | 61.92 | 64.84 | 70.23 | 59.43 | 52.98 | 43.41 | c | 43.90 | a | 51.95 | |||||||||||
| 1978 | 41.27 | c | 45.66 | 48.71 | 49.78 | 53.74 | 64.19 | c | 67.16 | c | 66.63 | 59.35 | 54.06 | 39.45 | 34.71 | c | 52.06 | |||||||||
| 1979 | 31.34 | 41.04 | 47.98 | 50.72 | 56.65 | 62.67 | 67.89 | 65.95 | 63.65 | 56.19 | 43.78 | a | 43.94 | 52.65 | ||||||||||||
| 1980 | 36.53 | 43.00 | 44.98 | 51.53 | 54.69 | 58.40 | 66.58 | 63.65 | 61.57 | 54.21 | 46.82 | 41.81 | 51.98 | |||||||||||||
| 1981 | 41.77 | 43.27 | 47.31 | 51.00 | c | 55.52 | 60.02 | 66.13 | a | 69.19 | 61.97 | 52.08 | 47.48 | a | 42.58 | 53.19 | ||||||||||
| 1982 | 37.89 | 41.55 | 45.53 | 46.78 | 56.27 | 63.93 | 65.42 | 66.60 | 62.25 | 52.94 | 43.32 | 41.10 | 51.96 | |||||||||||||
| 1983 | 43.06 | 46.57 | 49.48 | 50.98 | 58.55 | 60.50 | 64.58 | 67.02 | 59.87 | 52.13 | 47.95 | a | 35.92 | 53.05 | ||||||||||||
| 1984 | 42.77 | 44.47 | 49.40 | 48.72 | 53.76 | 59.45 | 66.02 | 66.58 | 61.47 | 50.37 | 44.65 | 37.05 | 52.06 | |||||||||||||
| 1985 | 35.29 | 39.59 | 43.60 | 52.27 | 56.16 | 62.20 | 70.40 | 65.87 | 58.65 | 51.73 | 38.10 | a | 34.13 | 50.67 | ||||||||||||
| 1986 | 43.00 | 43.84 | 51.00 | 49.47 | 56.06 | 65.47 | 63.53 | 70.27 | 59.03 | 54.47 | 47.18 | 39.84 | 53.60 | |||||||||||||
| 1987 | 39.68 | 45.07 | 47.52 | 53.50 | 59.56 | 64.45 | 65.92 | 67.66 | 63.78 | 56.73 | 46.97 | 38.76 | 54.13 | |||||||||||||
| 1988 | 39.10 | 43.41 | 46.63 | 51.78 | 54.61 | 61.13 | 67.08 | 65.92 | 62.12 | 57.18 | 46.77 | 39.77 | 52.96 | |||||||||||||
| 1989 | 41.39 | 35.52 | 45.21 | 54.97 | 56.52 | 64.23 | 64.26 | 64.29 | 64.67 | 52.87 | 46.60 | 38.84 | 52.45 | |||||||||||||
| 1990 | 42.85 | 41.77 | 48.65 | 52.87 | 54.98 | 61.78 | 69.35 | 68.26 | 65.58 | 51.19 | 46.45 | 33.37 | 53.09 | |||||||||||||
| 1991 | 39.53 | 48.12 | 44.71 | 49.25 | 52.89 | ----- | z | 67.90 | 68.26 | 64.95 | 54.31 | 46.90 | 40.92 | 52.52 | ||||||||||||
| 1992 | 43.45 | 47.79 | 51.27 | 53.75 | 60.94 | 66.00 | 68.85 | 68.87 | 60.78 | 54.69 | 45.38 | 38.98 | 55.06 | |||||||||||||
| 1993 | 36.11 | 40.16 | 48.68 | 50.72 | 59.48 | 60.75 | 62.84 | 67.48 | 63.43 | 56.24 | 39.42 | 39.58 | 52.07 | |||||||||||||
| 1994 | 43.65 | 40.93 | 49.32 | 51.87 | 58.58 | 60.37 | 68.68 | 67.10 | 64.55 | 51.76 | 40.63 | 42.16 | 53.30 | |||||||||||||
| 1995 | 44.52 | 46.44 | a | 47.71 | 49.48 | 58.68 | 62.57 | 68.53 | 64.95 | 65.42 | 53.00 | 50.92 | 42.34 | 54.55 | ||||||||||||
| 1996 | 41.47 | 41.76 | 47.63 | 51.66 | a | 53.66 | 61.47 | 70.32 | 68.00 | 59.67 | 52.69 | 44.50 | 41.61 | 52.87 | ||||||||||||
| 1997 | 41.13 | 43.34 | 46.44 | 49.52 | 61.05 | 60.87 | 66.90 | 69.94 | 64.48 | 52.50 | 48.80 | 39.65 | 53.72 | |||||||||||||
| 1998 | 44.00 | 45.98 | 47.65 | 50.90 | 55.66 | 62.65 | 69.97 | 68.73 | 65.35 | 53.42 | 47.60 | 19.87 | h | 55.63 | ||||||||||||
| 1999 | 45.02 | f | 43.86 | 45.44 | 50.40 | 53.40 | 59.60 | 65.65 | 67.29 | 63.28 | 54.03 | 49.42 | 43.32 | 54.15 | ||||||||||||
| 2000 | 40.98 | 43.78 | 44.84 | 52.40 | 56.37 | 64.30 | 66.68 | 66.44 | ----- | z | 53.84 | 42.65 | 40.94 | 52.11 | ||||||||||||
| 2001 | 41.55 | 42.64 | 47.66 | 43.97 | 58.65 | 59.57 | 66.23 | 67.76 | 64.30 | 52.69 | ----- | z | ----- | z | 54.50 | |||||||||||
| 2002 | ----- | z | ----- | z | 44.90 | 52.33 | 54.71 | 63.02 | 68.73 | 67.79 | 64.32 | ----- | z | 48.12 | 43.45 | 56.37 | ||||||||||
| 2003 | 46.00 | 44.64 | 48.45 | 50.15 | 56.89 | 65.68 | 69.82 | 68.69 | 64.70 | 56.58 | 43.78 | 41.37 | 54.73 | |||||||||||||
| 2004 | 39.19 | 44.84 | 50.31 | 54.27 | 57.58 | 64.13 | 70.58 | 70.79 | 61.38 | 55.13 | 44.48 | 42.37 | 54.59 | |||||||||||||
| 2005 | 41.53 | 43.39 | 49.03 | 50.87 | 59.00 | 60.27 | 68.79 | 69.56 | 61.27 | 55.05 | 43.45 | 40.10 | 53.53 | |||||||||||||
| 2006 | 44.74 | 42.27 | 45.18 | 52.37 | 58.42 | 64.43 | 69.98 | 66.98 | 64.22 | 53.15 | 46.83 | 40.13 | 54.06 | |||||||||||||
| 2007 | 37.95 | 44.59 | 49.66 | 50.80 | 57.24 | 61.92 | 70.00 | 67.77 | ----- | z | ----- | z | ----- | z | ----- | z | 54.99 | |||||||||
| Period of Record Statistics | ||||||||||||||||||||||||||
| MEAN | 40.07 | 43.15 | 46.60 | 50.10 | 56.08 | 61.77 | 66.91 | 66.89 | 62.23 | 53.15 | 45.29 | 40.11 | 52.60 | |||||||||||||
| S.D. | 3.30 | 2.56 | 2.29 | 2.51 | 2.26 | 2.29 | 2.16 | 2.24 | 2.51 | 1.85 | 2.70 | 2.73 | 1.19 | |||||||||||||
| SKEW | -0.68 | -0.15 | 0.11 | -0.47 | 0.26 | 0.09 | -0.08 | -0.29 | -0.30 | 0.25 | -0.69 | -0.64 | 0.16 | |||||||||||||
| MAX | 46.00 | 48.12 | 51.27 | 54.97 | 61.05 | 66.00 | 70.58 | 70.94 | 67.03 | 57.18 | 50.92 | 44.13 | 55.06 | |||||||||||||
| MIN | 31.34 | 35.52 | 42.12 | 43.97 | 51.98 | 57.00 | 62.27 | 62.30 | 56.87 | 49.24 | 38.10 | 33.37 | 50.26 | |||||||||||||
| NO YRS | 43 | 44 | 45 | 44 | 45 | 44 | 45 | 45 | 43 | 43 | 43 | 42 | 37 | |||||||||||||