| YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
| 1950 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1951 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1952 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1953 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1954 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1955 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | 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 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1958 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1959 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1960 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1961 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1962 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1963 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1964 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1965 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1966 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1967 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1968 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1969 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1970 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1971 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1972 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1973 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1974 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1975 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 9999.00 | |
| 1976 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 39.77 | a | 36.23 | h | 25.87 | 32.82 | ||
| 1977 | 19.65 | 30.43 | 26.94 | 37.53 | 39.42 | 51.07 | 51.90 | ----- | z | 40.89 | l | 37.41 | b | 26.23 | 23.94 | 34.45 | ||||||||||
| 1978 | 26.03 | 27.64 | 33.87 | 33.70 | 38.81 | 47.60 | 52.17 | h | 52.23 | 43.87 | 36.90 | 23.27 | 15.17 | a | 34.46 | |||||||||||
| 1979 | 10.55 | 23.96 | 30.35 | 33.93 | 42.06 | 48.52 | a | 50.62 | r | 53.58 | l | 48.74 | k | 39.24 | j | 26.10 | 27.72 | b | 30.40 | |||||||
| 1980 | 16.97 | a | 29.03 | 26.81 | 37.73 | 40.86 | b | 46.07 | 54.45 | 49.29 | 48.13 | 39.29 | 31.23 | 29.84 | 37.48 | |||||||||||
| 1981 | 29.26 | 26.57 | 32.06 | 34.93 | a | 40.77 | 45.10 | 51.87 | 57.77 | 44.48 | g | 35.10 | a | 31.28 | a | 23.89 | c | 37.15 | ||||||||
| 1982 | 20.07 | a | 19.64 | 28.87 | 30.73 | 39.94 | 50.50 | 53.26 | 55.00 | 46.30 | 36.77 | 27.00 | 24.10 | 36.01 | ||||||||||||
| 1983 | 29.03 | 29.86 | 32.39 | 33.70 | 43.13 | 46.57 | 51.19 | 58.00 | 43.70 | 40.23 | 31.40 | 15.16 | 37.86 | |||||||||||||
| 1984 | 23.32 | 26.48 | 31.52 | 32.20 | 38.55 | 45.70 | 55.03 | 55.65 | 44.03 | 33.90 | 29.07 | 18.39 | 36.15 | |||||||||||||
| 1985 | 18.35 | 19.61 | 26.68 | 37.10 | 42.65 | 48.90 | 60.52 | 50.32 | 41.47 | 35.65 | 17.80 | 19.17 | b | 34.85 | ||||||||||||
| 1986 | 27.42 | 26.75 | 35.06 | 33.50 | 43.13 | a | 53.77 | 50.55 | 59.03 | 42.87 | 40.29 | 28.30 | 24.42 | 38.76 | ||||||||||||
| 1987 | 20.90 | 28.75 | 29.74 | 39.83 | 44.97 | 51.20 | 53.74 | 51.55 | 51.10 | 42.29 | 32.03 | 24.00 | 39.18 | |||||||||||||
| 1988 | 21.68 | 28.28 | 28.90 | 36.80 | 40.13 | 49.90 | 54.68 | 53.97 | 47.10 | 45.19 | 29.80 | 23.35 | 38.31 | |||||||||||||
| 1989 | 22.94 | 16.14 | 28.52 | 37.10 | 39.61 | 48.87 | 55.03 | 51.58 | 47.90 | 37.58 | 32.03 | 26.81 | 37.01 | |||||||||||||
| 1990 | 25.48 | 23.64 | 30.71 | 39.73 | 39.03 | 47.60 | 57.00 | 55.87 | 53.67 | 36.32 | 31.10 | 12.94 | 37.76 | |||||||||||||
| 1991 | 20.94 | 33.57 | 28.68 | 34.37 | 39.45 | 43.70 | 55.39 | 57.65 | 49.37 | 37.81 | 28.07 | 26.26 | 37.94 | |||||||||||||
| 1992 | 25.68 | 32.24 | 35.39 | 38.33 | 45.35 | 52.93 | 51.84 | 55.65 | 46.33 | 41.35 | 27.73 | 21.13 | 39.50 | |||||||||||||
| 1993 | 17.61 | 19.43 | 31.61 | 33.90 | 46.10 | 45.67 | 46.13 | 50.81 | 47.00 | 40.71 | 24.30 | 26.84 | 35.84 | |||||||||||||
| 1994 | 29.65 | 22.86 | 31.29 | 38.03 | 43.87 | 46.67 | 57.35 | 55.35 | 50.67 | 37.74 | 23.27 | 21.90 | 38.22 | |||||||||||||
| 1995 | 24.68 | 28.43 | 28.48 | 33.60 | 42.90 | 45.87 | 53.84 | 50.23 | 49.30 | 35.77 | 32.93 | 23.94 | 37.50 | |||||||||||||
| 1996 | 23.23 | 22.48 | 30.29 | 35.07 | 38.61 | 47.50 | 55.32 | 54.84 | 45.63 | 37.97 | 29.27 | 23.55 | 36.98 | |||||||||||||
| 1997 | 23.40 | a | 25.32 | 29.16 | 32.80 | 43.45 | 45.90 | 51.94 | 54.97 | 48.57 | 35.13 | 31.53 | 22.13 | 37.02 | ||||||||||||
| 1998 | 23.81 | 28.18 | 29.23 | 34.37 | 41.06 | 46.27 | 59.32 | 55.87 | 52.67 | 36.61 | 31.80 | 21.58 | 38.40 | |||||||||||||
| 1999 | 26.79 | b | 24.29 | k | 28.10 | b | 30.80 | 36.90 | a | 43.83 | 50.35 | 56.13 | 44.73 | 38.68 | c | 34.60 | e | 24.17 | b | 37.74 | ||||||
| 2000 | 24.07 | c | 29.26 | b | 30.48 | h | 36.40 | 40.19 | 47.87 | 54.16 | 54.71 | 44.10 | 37.94 | 24.57 | 21.72 | b | 37.73 | |||||||||
| 2001 | 22.55 | 23.75 | 30.65 | 33.30 | 42.45 | 45.68 | b | 54.94 | 57.52 | 50.83 | 37.90 | b | 33.60 | 21.90 | b | 37.92 | ||||||||||
| 2002 | 24.32 | 23.71 | 25.45 | 34.80 | 40.16 | 49.20 | 57.97 | 52.65 | 48.73 | 35.13 | 31.77 | 27.58 | 37.62 | |||||||||||||
| 2003 | 29.87 | 25.25 | 32.13 | 35.10 | 41.16 | 50.67 | 60.19 | 57.90 | 50.87 | 42.39 | 25.07 | 26.00 | 39.72 | |||||||||||||
| 2004 | 23.19 | 26.83 | 32.74 | 36.80 | 40.71 | 49.17 | 57.65 | 56.16 | 46.57 | 39.52 | 29.93 | 28.55 | 38.98 | |||||||||||||
| 2005 | 26.19 | 26.64 | 31.97 | 34.10 | 43.42 | 46.00 | 56.03 | 55.97 | 46.40 | 40.19 | 28.50 | 22.26 | 38.14 | |||||||||||||
| 2006 | 28.90 | 23.04 | 28.90 | 35.90 | 43.84 | 50.57 | 59.23 | 54.58 | 49.37 | 37.48 | 28.70 | 24.87 | 38.78 | |||||||||||||
| 2007 | 19.48 | 28.39 | 32.94 | 35.70 | 42.52 | 48.00 | 61.23 | 54.90 | 46.83 | 37.52 | 28.67 | 23.58 | 38.31 | |||||||||||||
| 2008 | 20.06 | 28.03 | 26.81 | 29.77 | 41.94 | 46.67 | 55.77 | 54.61 | 47.83 | 39.71 | 34.13 | 19.48 | 37.07 | |||||||||||||
| 2009 | 23.90 | 27.04 | 25.81 | 33.37 | ----- | z | 48.93 | 57.23 | 55.94 | 51.40 | 35.35 | 30.37 | 18.65 | 37.09 | ||||||||||||
| 2010 | 29.74 | 29.54 | 31.68 | 34.55 | a | 38.42 | 46.53 | 54.32 | 53.52 | ----- | z | ----- | z | ----- | z | 26.39 | 38.30 | |||||||||
| 2011 | 24.43 | c | 21.76 | c | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 23.09 | |
| Period of Record Statistics | ||||||||||||||||||||||||||
| MEAN | 23.55 | 25.96 | 30.11 | 34.99 | 41.38 | 47.91 | 54.98 | 54.69 | 47.58 | 38.23 | 28.95 | 23.06 | 37.74 | |||||||||||||
| S.D. | 4.22 | 3.87 | 2.55 | 2.41 | 2.24 | 2.43 | 3.34 | 2.50 | 3.02 | 2.50 | 3.67 | 3.85 | 1.17 | |||||||||||||
| SKEW | -0.68 | -0.48 | 0.11 | 0.02 | 0.17 | 0.49 | -0.24 | -0.49 | 0.01 | 0.64 | -0.90 | -0.75 | -0.54 | |||||||||||||
| MAX | 29.87 | 33.57 | 35.39 | 39.83 | 46.10 | 53.77 | 61.23 | 59.03 | 53.67 | 45.19 | 34.60 | 29.84 | 39.72 | |||||||||||||
| MIN | 10.55 | 16.14 | 25.45 | 29.77 | 36.90 | 43.70 | 46.13 | 49.29 | 41.47 | 33.90 | 17.80 | 12.94 | 34.85 | |||||||||||||
| NO YRS | 35 | 34 | 33 | 34 | 33 | 34 | 32 | 32 | 30 | 33 | 33 | 35 | 26 | |||||||||||||