| YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
| 1952 | ----- | z | ----- | z | ----- | z | 49.42 | 57.80 | a | 64.80 | 71.72 | a | 72.53 | a | 64.32 | 53.58 | 34.28 | a | 31.00 | c | 55.49 | c | ||||
| 1953 | 37.31 | b | 33.98 | f | 44.92 | g | 52.90 | e | 52.76 | f | 65.17 | c | 73.32 | a | 70.73 | c | 63.20 | b | 51.57 | b | 42.95 | 25.48 | 53.63 | c | ||
| 1954 | 31.67 | a | 34.88 | 38.97 | b | 52.36 | b | 59.55 | 62.75 | 74.32 | 67.35 | a | 62.07 | 50.73 | a | 41.00 | 30.52 | 50.51 | ||||||||
| 1955 | 18.84 | 19.46 | a | 34.41 | b | 46.59 | a | 57.00 | 63.28 | 70.44 | 71.80 | a | 58.93 | i | 52.04 | s | 34.34 | b | 35.60 | b | 45.18 | b | ||||
| 1956 | 37.97 | a | 25.29 | a | 40.38 | c | 49.16 | h | 58.61 | 66.05 | 70.50 | 66.48 | a | 61.90 | 50.10 | f | 33.04 | b | 29.93 | b | 49.01 | b | ||||
| 1957 | 24.83 | e | 38.69 | a | 42.02 | e | ----- | z | 54.00 | a | 64.13 | 71.72 | a | 72.26 | 59.82 | 51.28 | b | 33.70 | 33.44 | d | 49.63 | a | ||||
| 1958 | 29.26 | 38.39 | 38.40 | a | 46.23 | 60.66 | 66.60 | 69.72 | b | 72.89 | 61.98 | a | 52.19 | 36.00 | 34.55 | 50.57 | ||||||||||
| 1959 | 33.05 | 34.62 | 41.26 | l | 50.47 | a | 53.65 | g | 69.08 | j | ----- | z | ----- | z | 58.59 | h | 49.77 | k | 38.50 | k | 29.15 | h | 39.38 | i | ||
| 1960 | 26.43 | k | 29.00 | a | 41.73 | 49.75 | 55.71 | 66.18 | 73.05 | a | 66.70 | h | 63.90 | 50.79 | c | 41.77 | 30.24 | 50.21 | b | |||||||
| 1961 | 29.87 | 35.95 | 41.06 | 47.91 | b | 57.79 | 68.84 | a | 74.14 | b | 72.73 | c | 56.34 | a | 47.82 | c | 34.57 | 26.04 | d | 49.42 | ||||||
| 1962 | 20.76 | b | 31.57 | a | 36.63 | a | 51.77 | f | ----- | z | 65.00 | l | 73.81 | e | 71.02 | b | 62.27 | b | 51.87 | a | ----- | z | 30.36 | f | 49.70 | e |
| 1963 | 22.40 | 37.36 | c | 37.43 | d | 43.90 | 60.00 | b | 61.45 | 72.67 | b | 73.52 | a | 65.48 | e | ----- | z | 39.94 | c | 25.60 | a | 49.07 | a | |||
| 1964 | 19.33 | a | ----- | z | 31.55 | a | 47.23 | ----- | z | ----- | z | 72.55 | 69.23 | c | 59.76 | a | 52.29 | 36.72 | 32.71 | 46.82 | c | |||||
| 1965 | 31.62 | a | 33.76 | a | 37.12 | a | 50.27 | 54.18 | a | 63.14 | a | 72.27 | 69.11 | 56.33 | 52.86 | b | 45.58 | 33.37 | a | 49.97 | ||||||
| 1966 | 29.78 | a | 30.23 | 41.26 | 48.53 | a | 59.82 | a | 65.28 | 73.18 | 69.39 | 63.36 | a | 48.75 | a | 41.77 | 28.06 | 49.95 | ||||||||
| 1967 | 25.65 | a | 32.93 | 43.68 | 45.83 | 54.03 | 62.22 | a | 72.85 | a | 72.18 | 62.68 | 51.00 | 41.30 | 23.82 | 49.01 | ||||||||||
| 1968 | 22.27 | 36.64 | a | 43.69 | 45.07 | 55.07 | b | 65.88 | b | 71.95 | a | 66.05 | a | 58.41 | a | 49.95 | a | 37.04 | d | 27.33 | d | 48.28 | ||||
| 1969 | 34.03 | a | 34.39 | 37.32 | c | 49.57 | c | 62.89 | c | 63.17 | 72.94 | 73.73 | a | 66.33 | c | 45.24 | 37.28 | a | 28.79 | c | 50.47 | |||||
| 1970 | 28.08 | a | 38.48 | 38.21 | 44.38 | d | 57.13 | 65.02 | a | 72.83 | d | 73.84 | 57.31 | a | 45.65 | 41.08 | 28.81 | 49.24 | ||||||||
| 1971 | 28.29 | 34.17 | a | 41.39 | d | 48.43 | 55.39 | 66.07 | 72.43 | a | 72.22 | a | 56.73 | b | 46.31 | b | 36.87 | c | 23.96 | g | 50.75 | a | ||||
| 1972 | 29.97 | n | 35.77 | g | 46.30 | c | 47.62 | e | 59.02 | c | 67.11 | b | 72.38 | e | 70.77 | i | 60.24 | a | 51.03 | b | ----- | z | 22.50 | b | 53.28 | d |
| 1973 | 19.67 | g | 31.96 | a | 38.80 | a | 44.62 | a | 56.56 | 63.71 | f | 68.54 | s | 70.93 | a | 59.87 | d | 51.98 | a | 39.54 | d | 32.23 | e | 47.39 | c | |
| 1974 | 25.65 | h | 30.81 | b | 44.83 | e | 49.54 | g | 59.32 | 68.12 | 72.58 | a | 67.90 | 61.98 | a | 52.15 | a | 40.43 | b | 27.98 | 52.61 | b | ||||
| 1975 | 21.71 | 33.24 | a | 40.03 | a | 43.00 | 53.38 | a | 61.82 | b | 73.72 | b | 68.66 | 61.50 | a | 49.37 | d | 35.50 | 27.80 | a | 47.48 | |||||
| 1976 | 21.06 | 30.79 | 34.40 | 47.07 | 57.35 | d | ----- | z | 73.29 | l | ----- | z | 59.06 | u | 47.00 | d | 39.87 | g | 28.65 | n | 39.61 | f | ||||
| 1977 | 23.70 | i | 19.81 | t | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
| Period of Record Statistics | ||||||||||||||||||||||||||
| MEAN | 27.39 | 32.98 | 39.53 | 47.67 | 57.39 | 64.85 | 72.50 | 70.69 | 61.17 | 50.16 | 38.32 | 29.32 | 49.49 | |||||||||||||
| S.D. | 5.87 | 4.59 | 3.60 | 2.70 | 2.54 | 2.07 | 1.17 | 2.41 | 2.87 | 2.46 | 3.51 | 3.55 | 1.02 | |||||||||||||
| SKEW | 0.18 | -1.24 | -0.20 | 0.15 | 0.17 | 0.08 | -0.73 | -0.48 | -0.22 | -0.74 | 0.21 | -0.05 | -0.72 | |||||||||||||
| MAX | 37.97 | 38.69 | 46.30 | 52.90 | 62.89 | 68.84 | 74.32 | 73.84 | 66.33 | 53.58 | 45.58 | 35.60 | 50.57 | |||||||||||||
| MIN | 18.84 | 19.46 | 31.55 | 43.00 | 53.38 | 61.45 | 69.72 | 66.05 | 56.33 | 45.24 | 33.04 | 22.50 | 47.48 | |||||||||||||
| YRS | 20 | 21 | 22 | 21 | 21 | 20 | 22 | 21 | 22 | 21 | 21 | 21 | 10 | |||||||||||||