YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
1956 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 56.83 | a | 33.79 | a | 25.37 | 38.67 | i | |
1957 | 11.71 | 22.22 | a | 30.98 | a | 47.69 | a | 58.40 | b | 67.81 | a | 77.40 | 71.11 | 60.25 | 49.00 | 32.90 | 26.85 | 46.36 | ||||||||
1958 | 23.06 | 15.75 | 32.32 | 48.27 | 62.21 | 63.07 | 69.85 | 72.58 | a | 63.58 | 54.05 | b | 35.57 | 15.79 | 46.34 | |||||||||||
1959 | 10.98 | 16.91 | 35.11 | 47.72 | 61.65 | 71.65 | 73.56 | 74.97 | 62.40 | 44.10 | 24.98 | 29.10 | 46.09 | |||||||||||||
1960 | 15.65 | 17.24 | 19.56 | 46.72 | 57.73 | 66.03 | 72.73 | 71.82 | 62.57 | 51.13 | 36.50 | a | 19.35 | 44.75 | ||||||||||||
1961 | 16.29 | 25.62 | 34.45 | 40.78 | 56.29 | 69.65 | 70.65 | 72.35 | 61.48 | 51.82 | 33.55 | 15.63 | 45.71 | |||||||||||||
1962 | 11.05 | 14.93 | 25.48 | 43.72 | 62.47 | 67.77 | 69.47 | 70.50 | 59.15 | 53.37 | 39.33 | 21.87 | 44.93 | |||||||||||||
1963 | 6.45 | 15.98 | 35.74 | 49.28 | 57.68 | 71.68 | 73.00 | 69.85 | 64.20 | 59.71 | 39.75 | 12.26 | 46.30 | |||||||||||||
1964 | 22.03 | 26.22 | 26.21 | 48.35 | 62.61 | 69.88 | 76.23 | 68.39 | 61.10 | 50.48 | 35.17 | 14.56 | 46.77 | |||||||||||||
1965 | 10.05 | 12.95 | 18.32 | 43.45 | 60.58 | 69.00 | 72.05 | 69.03 | 53.62 | 52.94 | 33.83 | a | 28.06 | 43.66 | ||||||||||||
1966 | 3.37 | 15.68 | 37.29 | 42.37 | 55.94 | 69.05 | 76.16 | 67.63 | 61.40 | 49.31 | 30.42 | 18.37 | 43.91 | |||||||||||||
1967 | 16.52 | 11.79 | 31.90 | 46.15 | 53.92 | 67.40 | 70.44 | 68.03 | 60.82 | 48.61 | 33.00 | 23.05 | 44.30 | |||||||||||||
1968 | 15.37 | 16.17 | 40.92 | 50.02 | 55.08 | 68.60 | 70.87 | 70.87 | 61.53 | 51.77 | 34.73 | 18.56 | 46.21 | |||||||||||||
1969 | 8.27 | 18.89 | 22.29 | 49.42 | 61.27 | 62.13 | 73.32 | 73.26 | 62.97 | 46.89 | 34.10 | 19.40 | 44.35 | |||||||||||||
1970 | 4.44 | 15.91 | 23.61 | 45.35 | 59.89 | 71.68 | 74.39 | 70.56 | 61.68 | 49.27 | 31.88 | 17.02 | 43.81 | |||||||||||||
1971 | 6.93 | a | 18.23 | 29.10 | a | 48.35 | 56.73 | 71.63 | 68.87 | 69.60 | 62.03 | a | 54.15 | 33.77 | 18.13 | 44.79 | ||||||||||
1972 | 7.97 | 12.31 | 28.73 | 43.38 | 62.21 | 68.05 | 70.58 | 70.29 | 59.93 | 46.23 | 32.82 | 13.06 | 42.96 | |||||||||||||
1973 | 19.00 | 23.48 | 40.71 | 45.65 | 57.23 | 70.58 | 72.55 | 73.02 | 60.85 | 54.98 | 34.85 | 16.55 | 47.45 | |||||||||||||
1974 | 11.23 | 17.52 | 30.39 | 47.88 | 55.19 | 67.52 | 77.19 | 66.94 | 58.43 | 51.82 | 34.33 | 23.52 | 45.16 | |||||||||||||
1975 | 14.44 | 15.27 | 22.27 | 38.05 | 62.47 | 68.23 | 75.52 | 70.85 | 57.83 | 52.42 | 36.30 | 20.18 | 44.49 | |||||||||||||
1976 | 12.63 | 27.90 | 32.35 | 51.62 | 58.69 | 71.23 | 75.15 | 71.22 | a | 60.90 | 43.63 | 26.68 | 13.37 | a | 45.45 | |||||||||||
1977 | -0.81 | 23.00 | 36.29 | 53.45 | 67.02 | 69.37 | 74.37 | 66.39 | 61.03 | 47.16 | 31.52 | 14.52 | 45.28 | |||||||||||||
1978 | 3.94 | 9.14 | 28.74 | 44.17 | 60.79 | 68.65 | 70.65 | 70.65 | 65.97 | 49.44 | 30.50 | 13.26 | 42.99 | |||||||||||||
1979 | 0.52 | 6.91 | 25.34 | 40.83 | 55.24 | 67.81 | a | 72.24 | 67.15 | 61.64 | a | 47.29 | 30.62 | 25.29 | 41.74 | |||||||||||
1980 | 15.73 | 14.43 | 26.52 | 48.68 | 61.61 | 69.10 | 75.02 | 70.56 | 61.57 | 45.76 | 37.41 | a | 19.38 | a | 45.48 | |||||||||||
1981 | 18.29 | 24.44 | a | 38.73 | 50.73 | 58.95 | 68.58 | 72.89 | 70.00 | 60.70 | 49.08 | e | 39.27 | 16.95 | 47.38 | |||||||||||
1982 | -0.10 | 14.19 | a | 30.31 | 43.88 | 62.77 | 64.23 | 74.64 | b | 70.06 | 59.27 | 50.60 | 29.52 | b | 26.27 | 43.80 | ||||||||||
1983 | 19.60 | 25.88 | 33.52 | 43.02 | 56.93 | b | 69.50 | 78.60 | 77.10 | a | 63.45 | 49.06 | 34.60 | d | -0.20 | f | 50.11 | a | ||||||||
1984 | 14.65 | h | 27.46 | b | 24.29 | 46.82 | 59.00 | a | 69.95 | 73.15 | 74.23 | a | 57.25 | 52.37 | a | 34.81 | c | 21.80 | c | 49.19 | a | |||||
1985 | 12.66 | c | 17.19 | b | 37.02 | 53.86 | b | 65.10 | b | 65.28 | a | 72.98 | 67.15 | 60.00 | a | 47.60 | a | 22.80 | c | 6.85 | d | 44.04 | ||||
1986 | 18.63 | e | 16.69 | b | 35.26 | b | 48.55 | 60.73 | 70.75 | 74.72 | a | 68.08 | 61.20 | c | 50.78 | a | 27.46 | c | 24.39 | 46.44 | ||||||
1987 | 22.03 | b | 32.33 | a | 39.32 | 55.00 | 64.65 | a | 73.60 | 77.10 | a | 69.21 | 63.25 | 45.10 | 37.47 | a | 24.67 | b | 50.31 | |||||||
1988 | 8.60 | b | 10.46 | d | 34.00 | b | 47.74 | a | 65.87 | 76.08 | 77.45 | 74.58 | 62.91 | b | 43.43 | c | 31.48 | a | 22.37 | a | 46.25 | |||||
1989 | 23.21 | 11.04 | e | 26.47 | b | 46.65 | c | 58.57 | a | 68.50 | a | 76.50 | b | 70.50 | 60.28 | 50.39 | 29.87 | 9.48 | 44.29 | |||||||
1990 | 27.31 | 27.23 | b | 35.03 | 48.97 | 58.05 | 70.60 | 71.60 | 70.68 | 65.50 | 46.97 | 36.67 | 15.67 | a | 47.85 | |||||||||||
1991 | 11.73 | a | 26.50 | a | 34.21 | 48.77 | 62.50 | 73.63 | 73.87 | 71.00 | 59.33 | 48.50 | 23.84 | a | 20.18 | a | 46.17 | |||||||||
1992 | 21.92 | 27.62 | a | 33.33 | b | 43.13 | c | 60.76 | 65.63 | 65.26 | 65.21 | 57.61 | c | 47.40 | a | 29.82 | e | 18.74 | d | 44.70 | ||||||
1993 | 10.63 | e | 12.82 | c | 25.97 | a | 42.24 | a | 57.41 | c | 63.98 | 69.45 | b | 69.59 | d | 54.79 | b | 45.88 | c | 28.88 | b | 19.10 | a | 41.73 | ||
1994 | 1.67 | e | 6.27 | d | 32.15 | a | 44.09 | b | 60.57 | b | 68.93 | a | 69.02 | b | 66.64 | b | 63.29 | d | 49.88 | a | 36.31 | c | 22.30 | c | 43.43 | |
1995 | 15.74 | b | 17.81 | b | 31.35 | 39.57 | b | 55.23 | e | 71.22 | a | 72.29 | 72.95 | a | 58.22 | a | 46.88 | a | 24.39 | c | 16.71 | e | 43.53 | |||
1996 | 8.07 | d | 15.79 | e | 23.78 | b | 39.35 | 53.92 | 68.29 | f | 68.54 | c | 69.23 | 59.89 | b | 47.26 | b | 23.58 | f | 11.85 | e | 39.77 | b | |||
1997 | 9.29 | e | 18.42 | d | 28.41 | b | 42.23 | b | 52.43 | a | 70.06 | c | 70.38 | b | 69.04 | c | 61.86 | b | 48.54 | c | 26.97 | 26.66 | c | 43.69 | ||
1998 | 15.00 | f | 28.88 | d | 27.45 | 48.67 | 65.50 | a | 65.59 | a | 72.67 | b | 72.10 | a | 64.29 | b | 50.67 | b | 36.20 | b | 24.35 | a | 50.58 | a | ||
1999 | 10.92 | g | 26.64 | 31.87 | a | 47.55 | a | 58.95 | b | 66.37 | d | 75.18 | c | 69.19 | e | 59.68 | b | 47.43 | d | 41.37 | d | 24.77 | c | 49.91 | a | |
2000 | 13.08 | e | 24.96 | b | 39.17 | b | 43.92 | f | 59.81 | b | 65.19 | c | 71.89 | c | 70.05 | c | 59.70 | e | 51.04 | c | 30.24 | e | 5.98 | c | 44.65 | a |
2001 | 17.32 | f | 7.60 | c | 23.83 | a | 46.57 | 59.55 | 68.41 | a | 73.85 | 71.72 | d | 60.02 | d | 46.16 | i | 44.48 | j | 27.45 | k | 51.44 | d | |||
2002 | ----- | z | 24.71 | i | 23.64 | m | 40.16 | k | 53.33 | g | 69.02 | d | 75.44 | d | 69.46 | e | 62.61 | h | 40.70 | d | 31.61 | h | 24.44 | g | 63.66 | h |
2003 | 13.30 | d | 14.26 | c | 27.82 | a | 46.25 | d | 55.68 | c | 66.52 | e | 71.57 | c | 73.14 | c | 59.80 | c | 48.88 | b | 31.09 | g | ----- | z | 47.72 | b |
2004 | ----- | z | 15.79 | e | 35.06 | d | ----- | z | 54.98 | g | 63.72 | e | 69.83 | b | 63.10 | e | 65.34 | a | 49.03 | 35.67 | 21.76 | d | 46.59 | c | ||
2005 | 14.11 | h | 22.28 | e | 28.69 | d | 49.30 | e | 54.24 | f | 71.93 | c | 73.52 | f | 68.67 | d | 64.30 | 49.22 | f | 35.36 | a | 16.55 | a | 44.63 | d | |
2006 | 25.98 | c | 17.15 | b | 29.42 | e | 50.66 | b | 58.08 | f | 69.28 | 75.43 | b | 70.74 | 57.60 | 44.52 | d | 34.23 | 26.34 | 45.58 | a | |||||
2007 | 17.03 | a | 8.00 | a | 34.02 | 43.64 | a | 62.86 | b | 69.67 | a | 72.45 | 68.66 | 61.37 | c | 51.97 | 33.15 | 14.35 | a | 44.76 | ||||||
2008 | 10.32 | a | 13.58 | j | 26.91 | b | 41.03 | 55.31 | 67.20 | 73.32 | 69.52 | 61.35 | 47.53 | 32.73 | 10.71 | b | 45.08 | a | ||||||||
2009 | 5.50 | 18.39 | 28.69 | 44.72 | 58.18 | 66.33 | 67.60 | 67.31 | 63.93 | 41.06 | 39.93 | 14.82 | 43.04 | |||||||||||||
2010 | 7.90 | 11.52 | 34.58 | 52.72 | 59.23 | 68.25 | 74.40 | 74.16 | 58.52 | 50.71 | 31.82 | 12.44 | 44.69 | |||||||||||||
2011 | 7.34 | 13.48 | 24.41 | b | 43.07 | 56.24 | 67.87 | 77.74 | 70.81 | 60.25 | 51.18 | 35.38 | 24.27 | 44.34 | ||||||||||||
2012 | 21.24 | 24.12 | 44.29 | 48.10 | 62.97 | 70.78 | 78.92 | 69.98 | 60.45 | 45.27 | 34.17 | 19.06 | 48.28 | |||||||||||||
2013 | 14.05 | 14.18 | 21.82 | 36.68 | 55.53 | 67.55 | 73.26 | 71.58 | 64.72 | 46.81 | 29.57 | 10.13 | 42.16 | |||||||||||||
2014 | 6.76 | 6.04 | 22.39 | 41.17 | 56.68 | 68.93 | 70.18 | 71.47 | 60.97 | 47.42 | 23.02 | 22.30 | a | 41.44 | ||||||||||||
2015 | 16.23 | 9.11 | 31.58 | 45.65 | 55.23 | 68.35 | 69.28 | f | 67.98 | 65.32 | 49.07 | a | 35.75 | 24.37 | a | 42.60 | a | |||||||||
2016 | 15.69 | 23.43 | 37.94 | 46.85 | 59.24 | 70.00 | 72.27 | 70.81 | 63.82 | 49.98 | f | 42.20 | 16.08 | a | 47.12 | a | ||||||||||
2017 | 17.77 | 29.07 | 31.03 | 47.75 | 56.77 | 69.62 | 73.00 | 66.92 | 64.47 | 49.39 | 32.02 | 18.32 | 46.34 | |||||||||||||
2018 | 13.35 | 12.36 | 29.47 | 34.43 | 65.95 | 70.98 | 74.00 | d | 71.27 | 66.40 | f | 44.15 | e | 26.12 | 22.92 | 42.27 | a | |||||||||
2019 | 11.94 | 7.39 | 25.48 | 44.87 | 53.97 | 68.95 | 73.37 | 68.89 | 64.83 | 44.65 | 28.87 | 19.15 | 42.70 | |||||||||||||
2020 | 17.02 | 17.43 | 34.92 | 43.12 | 57.94 | 72.97 | 75.03 | 71.84 | 60.28 | 42.61 | 37.83 | 24.60 | 46.30 | |||||||||||||
2021 | 20.98 | 9.77 | 38.15 | 45.95 | 59.32 | 74.88 | 73.61 | 72.21 | 64.95 | 54.53 | 35.73 | 22.45 | 47.71 | |||||||||||||
2022 | 7.55 | 12.54 | a | 30.87 | 38.72 | 59.58 | 71.34 | a | 74.13 | 70.16 | 63.57 | 49.11 | 34.22 | 14.60 | 43.87 | |||||||||||
2023 | 15.84 | 16.05 | 24.55 | 42.90 | a | 62.15 | 73.23 | 72.15 | 72.63 | 66.80 | 50.42 | 36.27 | 32.27 | 47.10 | ||||||||||||
2024 | 17.17 | a | 30.84 | 35.60 | 44.08 | r | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 27.87 | i | ||
Period of Record Statistics | ||||||||||||||||||||||||||
MEAN | 12.99 | 17.70 | 30.71 | 45.72 | 59.25 | 68.96 | 73.11 | 70.26 | 61.42 | 48.92 | 33.04 | 19.20 | 45.01 | |||||||||||||
S.D. | 6.51 | 6.76 | 5.65 | 4.16 | 3.39 | 2.75 | 2.75 | 2.42 | 2.61 | 3.61 | 4.40 | 5.58 | 1.83 | |||||||||||||
SKEW | -0.05 | 0.28 | 0.02 | -0.25 | 0.26 | -0.06 | -0.19 | -0.05 | -0.36 | 0.20 | -0.43 | -0.14 | 0.31 | |||||||||||||
MAX | 27.31 | 32.33 | 44.29 | 55.00 | 67.02 | 76.08 | 78.92 | 77.10 | 66.80 | 59.71 | 42.20 | 32.27 | 50.31 | |||||||||||||
MIN | -0.81 | 6.04 | 18.32 | 34.43 | 52.43 | 62.13 | 65.26 | 63.10 | 53.62 | 40.70 | 22.80 | 5.98 | 41.44 | |||||||||||||
YRS | 61 | 66 | 67 | 64 | 63 | 66 | 65 | 67 | 65 | 65 | 64 | 64 | 51 |