| YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
| 1948 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 55.58 | 51.68 | 44.67 | 34.68 | 19.70 | 8.26 | 35.76 | f | ||||||
| 1949 | -7.06 | 5.79 | 21.13 | 35.20 | 41.00 | b | 50.47 | m | 58.00 | h | 53.36 | c | 49.80 | 32.55 | 27.73 | 14.23 | a | 27.37 | b | |||||||
| 1950 | 10.55 | 22.50 | 21.32 | 29.37 | 38.35 | 40.27 | 49.48 | b | 53.86 | c | 46.41 | a | 39.21 | c | 29.59 | c | 24.62 | o | 34.63 | a | ||||||
| 1951 | 17.00 | g | ----- | z | 27.81 | 38.79 | f | 44.26 | 48.96 | c | 59.07 | b | 55.15 | e | 50.30 | c | 36.80 | a | 25.96 | b | 16.45 | 40.53 | c | |||
| 1952 | 9.90 | 19.97 | 25.74 | 37.80 | 45.76 | b | 53.85 | c | 58.04 | e | 56.13 | p | 47.20 | e | 39.92 | g | 27.50 | v | 20.44 | v | 37.28 | d | ||||
| 1953 | 22.06 | 21.89 | 27.90 | 34.73 | 36.71 | 50.52 | a | 59.77 | a | 53.68 | 47.69 | a | 35.60 | a | 28.24 | a | 15.13 | 36.16 | ||||||||
| 1954 | 19.00 | 24.64 | 25.13 | 38.27 | 43.61 | 58.17 | 65.03 | 56.06 | 46.28 | a | 34.16 | 27.43 | 16.97 | 37.90 | ||||||||||||
| 1955 | 5.52 | 18.75 | 26.04 | d | 32.40 | 41.77 | ----- | z | 59.08 | e | ----- | z | ----- | z | 38.67 | a | 24.40 | ----- | z | 30.83 | d | |||||
| 1956 | 24.26 | d | 18.52 | 26.84 | 36.47 | 45.32 | 51.80 | 55.81 | 54.94 | 46.43 | 36.32 | 21.80 | 16.73 | t | 38.05 | a | ||||||||||
| 1957 | 12.00 | i | 27.89 | 30.75 | c | 35.86 | h | 34.52 | 47.97 | 49.04 | c | 51.65 | 45.83 | l | 36.35 | 25.10 | ----- | z | 37.91 | d | ||||||
| 1958 | 21.77 | r | 28.15 | a | 26.43 | a | 33.21 | a | 42.92 | e | 54.48 | e | 57.38 | e | 57.75 | g | 49.04 | f | 41.00 | g | 26.64 | b | 22.17 | a | 36.42 | d |
| 1959 | 24.00 | 19.75 | 30.35 | e | 37.05 | i | 42.48 | 53.83 | 60.41 | b | 56.28 | f | 46.87 | 37.16 | 24.30 | 19.42 | 35.86 | b | ||||||||
| 1960 | 14.39 | 22.76 | 32.52 | 38.20 | 43.39 | 56.70 | 55.84 | 54.70 | a | 50.36 | b | 37.68 | 27.70 | 19.48 | 37.81 | |||||||||||
| 1961 | 18.23 | 25.60 | c | 29.68 | c | 35.84 | e | 43.55 | 57.39 | b | 60.92 | e | 56.35 | 44.83 | 37.20 | a | 24.17 | 19.21 | b | 37.75 | ||||||
| 1962 | 18.00 | 23.07 | 24.16 | 35.03 | 40.26 | d | ----- | z | ----- | z | ----- | z | 47.77 | 40.52 | 26.90 | ----- | z | 31.96 | d | |||||||
| 1963 | 9.55 | 29.43 | 26.45 | 31.50 | b | 44.21 | b | 47.14 | a | 55.07 | c | 54.74 | d | 49.80 | e | 41.86 | b | 27.25 | b | 19.87 | a | 36.41 | ||||
| 1964 | 15.45 | 19.34 | 23.55 | 31.96 | d | 43.34 | b | 52.14 | a | 56.76 | j | 56.83 | h | 46.14 | a | 41.30 | d | 22.80 | 21.13 | 31.72 | b | |||||
| 1965 | 22.45 | 26.56 | j | 28.32 | 35.13 | 39.55 | ----- | z | 55.45 | 55.42 | 44.13 | 37.94 | 31.73 | 18.77 | e | 36.89 | b | |||||||||
| 1966 | 16.16 | ----- | z | 30.03 | 36.50 | 46.58 | 51.63 | 56.77 | 57.29 | 46.60 | 37.27 | e | 30.30 | j | 23.72 | b | 40.26 | b | ||||||||
| 1967 | 18.84 | 22.39 | 29.90 | 28.10 | 42.77 | 48.54 | b | 59.81 | 58.50 | a | 50.90 | a | 38.03 | 31.28 | a | ----- | z | 39.01 | a | |||||||
| 1968 | 17.23 | 29.48 | 28.06 | 34.43 | 42.77 | e | 54.47 | 60.39 | c | 53.58 | 47.17 | 38.03 | ----- | z | 11.39 | h | 40.56 | b | ||||||||
| 1969 | 20.52 | 17.52 | a | 22.06 | 35.33 | 44.33 | a | 49.89 | b | ----- | z | 55.16 | l | 48.84 | e | 32.55 | k | 23.63 | 16.61 | 30.97 | c | |||||
| 1970 | 18.03 | 27.29 | 28.18 | n | 29.13 | 45.52 | 51.93 | a | 60.64 | c | 59.00 | a | 43.43 | 32.90 | 26.00 | 14.48 | 37.12 | a | ||||||||
| 1971 | 19.94 | ----- | z | 27.03 | 33.17 | 39.65 | ----- | z | 59.85 | d | ----- | z | 46.67 | 29.59 | d | 24.37 | 14.06 | 32.70 | c | |||||||
| 1972 | 16.23 | a | 23.17 | 34.03 | 35.85 | c | 44.32 | 55.17 | 61.39 | 57.35 | 47.45 | a | 37.16 | 26.38 | a | 14.96 | g | 39.86 | a | |||||||
| 1973 | 8.45 | b | 21.50 | d | 26.97 | b | 34.58 | f | 44.93 | b | 48.82 | s | 57.07 | d | 54.00 | b | 45.52 | a | ----- | z | 25.04 | b | 20.39 | h | 35.43 | d |
| 1974 | 16.74 | 20.32 | 33.45 | 34.83 | 45.60 | p | 48.70 | c | 54.84 | 52.06 | 49.42 | d | 38.04 | f | 27.10 | 17.35 | 35.48 | b | ||||||||
| 1975 | 16.57 | a | 21.56 | a | 27.07 | a | 28.30 | 39.95 | i | 51.36 | p | 59.87 | 56.23 | 50.03 | 33.39 | c | 23.97 | a | 25.25 | w | 35.22 | c | ||||
| 1976 | 19.46 | c | 25.35 | i | 26.06 | 30.57 | g | 42.94 | 47.17 | r | 57.93 | c | 51.50 | i | 49.68 | e | 37.00 | d | 24.21 | a | 14.40 | f | 36.75 | e | ||
| 1977 | 18.96 | c | 23.11 | 23.19 | 37.23 | d | 38.97 | 51.68 | k | 54.71 | q | 54.87 | p | 46.29 | i | 38.70 | u | 26.25 | r | 25.23 | e | 27.78 | f | |||
| 1978 | ----- | z | 24.46 | 31.58 | 30.39 | b | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 40.33 | d | ----- | z | ----- | z | 31.69 | h | ||
| 1979 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 23.90 | 19.90 | 21.90 | j | ||
| 1980 | 25.29 | 27.97 | 26.77 | 37.13 | 40.77 | 48.97 | 59.29 | 56.90 | 47.97 | 37.74 | 26.33 | 23.58 | 38.23 | |||||||||||||
| 1981 | 22.90 | 25.29 | 30.27 | a | 38.93 | 45.84 | 57.67 | 59.19 | 57.16 | 52.63 | 36.03 | 28.00 | 22.29 | 39.68 | ||||||||||||
| 1982 | 16.29 | 25.29 | 27.81 | 35.50 | 44.23 | 52.57 | 58.39 | 56.54 | g | 50.62 | a | ----- | z | ----- | z | ----- | z | 38.84 | d | |||||||
| 1983 | 23.06 | m | 28.46 | b | 31.78 | d | 32.56 | l | ----- | z | ----- | z | 55.05 | l | 55.19 | 50.21 | a | 37.71 | 27.47 | 23.61 | 36.35 | e | ||||
| 1984 | 21.00 | 22.21 | a | 31.35 | 33.46 | b | 49.71 | 53.27 | 60.13 | 57.42 | l | 50.77 | 35.00 | 23.90 | 16.35 | 36.11 | a | |||||||||
| 1985 | 18.03 | 22.00 | 25.72 | b | 39.37 | ----- | z | ----- | z | 60.68 | c | 54.94 | 45.43 | 36.37 | a | ----- | z | ----- | z | 37.82 | d | |||||
| 1986 | ----- | z | 28.86 | 33.72 | b | 37.04 | b | 44.21 | b | 53.50 | f | 56.00 | e | 57.34 | b | 45.36 | b | 35.33 | a | 27.80 | 18.36 | t | 40.63 | c | ||
| 1987 | ----- | z | ----- | z | 28.90 | 35.57 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 38.44 | v | 28.79 | b | 15.48 | 27.18 | h | |||
| 1988 | ----- | z | ----- | z | 29.29 | x | 36.33 | u | 36.19 | o | 48.82 | h | 58.67 | y | 55.96 | d | 47.91 | h | ----- | z | 26.43 | 14.19 | d | 32.19 | i | |
| 1989 | 12.87 | 22.39 | 32.48 | b | 41.67 | f | 46.52 | f | 53.71 | b | 60.68 | 56.26 | 49.21 | a | 36.87 | 26.50 | 20.29 | g | 39.00 | c | ||||||
| 1990 | 18.47 | a | 22.18 | 33.17 | a | 40.67 | 44.43 | c | 54.79 | a | 60.87 | a | 56.10 | 51.70 | c | 38.26 | 25.83 | 13.74 | 38.35 | |||||||
| 1991 | 18.52 | 26.93 | 28.61 | 35.17 | 42.60 | f | 52.30 | 55.95 | l | 58.46 | c | 50.29 | i | 42.90 | b | 26.73 | 20.03 | 34.41 | c | |||||||
| 1992 | 14.58 | 29.90 | 33.87 | 43.60 | 50.06 | 51.96 | c | 56.93 | b | 58.61 | c | 50.46 | b | 42.97 | b | 26.00 | 18.39 | 39.78 | ||||||||
| 1993 | 20.52 | 25.75 | 34.37 | a | 38.12 | d | 45.82 | c | ----- | z | 59.03 | a | 55.05 | i | 47.00 | i | 37.38 | g | 21.23 | 17.53 | n | 34.98 | e | |||
| 1994 | 15.90 | b | 22.65 | k | 32.28 | m | 37.76 | e | 44.83 | g | 53.83 | l | 60.71 | j | 59.87 | p | 47.68 | e | 35.17 | h | 19.41 | a | 18.05 | i | 30.19 | h |
| 1995 | ----- | z | 28.24 | c | 31.68 | 33.72 | a | 41.62 | b | 45.76 | a | 58.77 | 55.96 | d | 50.47 | 38.00 | b | 30.76 | e | 22.48 | d | 39.77 | a | |||
| 1996 | 22.61 | h | 28.38 | c | 31.63 | a | 40.34 | a | 41.73 | p | 51.93 | p | 58.70 | d | 59.06 | 47.50 | 37.97 | a | 28.43 | b | 24.72 | m | 41.50 | d | ||
| 1997 | 22.17 | b | 26.23 | b | ----- | z | ----- | z | ----- | z | 54.60 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 15.32 | 29.58 | h | ||
| 1998 | 21.00 | f | 24.21 | 30.17 | a | 33.04 | e | 38.37 | a | 48.53 | 58.81 | 56.50 | g | 50.77 | 34.52 | b | 24.43 | 16.03 | b | 35.89 | b | |||||
| 1999 | 20.69 | b | 23.68 | 26.74 | d | 32.77 | 44.81 | e | 52.93 | 60.54 | e | 54.68 | 49.88 | m | 41.41 | b | 27.63 | ----- | z | 38.59 | b | |||||
| 2000 | 33.87 | h | 37.54 | a | 44.03 | b | 49.06 | l | 53.23 | e | 55.05 | j | 56.74 | 54.92 | e | ----- | z | 34.29 | x | 22.55 | a | 22.57 | q | 44.84 | f | |
| 2001 | 20.70 | h | 22.75 | 33.64 | c | 35.15 | d | 51.55 | i | 56.23 | h | ----- | z | 59.71 | ----- | z | ----- | z | 36.97 | 35.57 | x | 37.64 | g | |||
| 2002 | ----- | z | 20.88 | d | ----- | z | 39.53 | m | 46.52 | f | 54.52 | e | 57.32 | 57.42 | 48.83 | 37.55 | 28.10 | i | 23.08 | g | 46.09 | f | ||||
| 2003 | 25.65 | e | 24.22 | a | 32.91 | h | 33.00 | a | 45.95 | j | 57.59 | m | 64.07 | q | 57.08 | g | 51.60 | 43.38 | r | ----- | z | ----- | z | 33.62 | h | |
| 2004 | 18.97 | a | 23.56 | b | 36.06 | 37.07 | b | ----- | z | ----- | z | 55.50 | a | 57.32 | f | 46.44 | e | 39.91 | h | 27.40 | 20.48 | 33.19 | d | |||
| 2005 | 25.00 | v | ----- | z | 28.33 | y | 33.48 | c | 45.50 | c | ----- | z | 60.62 | w | 53.76 | j | 43.88 | m | 38.83 | y | 30.08 | d | 21.00 | u | 36.35 | i |
| 2006 | 14.07 | p | 20.88 | k | 25.11 | d | 38.07 | a | 46.27 | i | 52.54 | q | ----- | z | 55.00 | i | 46.91 | s | 34.93 | c | 26.55 | a | 18.26 | 28.58 | g | |
| 2007 | 15.07 | b | 25.20 | c | 33.53 | a | 36.24 | i | 47.20 | p | 58.14 | w | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 24.60 | i |
| Period of Record Statistics | ||||||||||||||||||||||||||
| MEAN | 17.15 | 23.98 | 29.12 | 35.16 | 43.31 | 51.97 | 58.15 | 55.79 | 48.19 | 37.20 | 26.26 | 18.26 | 38.01 | |||||||||||||
| S.D. | 5.90 | 4.60 | 4.23 | 3.27 | 3.52 | 3.77 | 2.93 | 2.07 | 2.29 | 2.78 | 3.09 | 3.70 | 1.24 | |||||||||||||
| SKEW | -1.81 | -0.73 | 0.64 | -0.09 | 0.13 | -0.82 | -1.03 | -0.11 | -0.10 | -0.09 | 0.53 | -0.25 | -0.01 | |||||||||||||
| MAX | 25.65 | 37.54 | 44.03 | 43.60 | 53.23 | 58.17 | 65.03 | 59.71 | 52.63 | 42.97 | 36.97 | 25.23 | 39.78 | |||||||||||||
| MIN | -7.06 | 5.79 | 21.13 | 28.10 | 34.52 | 40.27 | 49.04 | 51.65 | 43.43 | 29.59 | 19.41 | 8.26 | 36.16 | |||||||||||||
| YRS | 42 | 48 | 51 | 46 | 40 | 33 | 42 | 36 | 43 | 41 | 49 | 33 | 9 | |||||||||||||