YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
1925 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1926 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1927 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1928 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1929 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1930 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1931 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1932 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1933 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1934 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 66.34 | b | 67.00 | 52.43 | 46.84 | 34.77 | 25.39 | 48.80 | f | |||||
1935 | ----- | z | 27.50 | b | 35.68 | c | 40.27 | 45.83 | a | 61.30 | 65.71 | 65.23 | 54.59 | a | 43.33 | a | 29.14 | a | 25.00 | a | 44.87 | a | ||||
1936 | 20.83 | b | 19.04 | a | 32.55 | 38.83 | 52.37 | a | 59.87 | 58.36 | f | 64.13 | ----- | z | 38.87 | a | 28.03 | 24.77 | 37.93 | b | ||||||
1937 | 12.13 | 23.46 | 28.32 | 40.17 | 52.32 | 59.55 | a | 64.81 | 65.13 | a | ----- | z | 42.76 | f | 28.52 | a | 21.48 | b | 39.59 | b | ||||||
1938 | 22.83 | a | 24.46 | b | 35.52 | 38.73 | 48.45 | 60.00 | 63.19 | 64.16 | 56.67 | 47.07 | b | 26.90 | a | 25.33 | a | 42.78 | ||||||||
1939 | 26.53 | a | 18.85 | b | 31.48 | b | 41.37 | 51.16 | 57.80 | 62.29 | 60.32 | 56.27 | 40.50 | a | 27.47 | 24.23 | a | 41.52 | ||||||||
1940 | 16.21 | b | 24.82 | a | 31.35 | 37.58 | d | 48.77 | a | 57.53 | 64.45 | 59.29 | 55.14 | a | 42.55 | 28.03 | a | 27.17 | b | 41.07 | ||||||
1941 | 24.06 | 28.71 | 29.84 | 38.40 | 52.43 | a | 55.97 | 60.77 | 59.74 | 52.97 | 44.03 | a | 31.43 | 25.26 | 41.97 | |||||||||||
1942 | 19.32 | 19.96 | 29.09 | i | 41.77 | 44.68 | 57.90 | 60.81 | 61.68 | 51.40 | 41.35 | 30.60 | 22.94 | 41.13 | a | |||||||||||
1943 | 19.68 | 26.50 | 26.55 | 40.83 | 48.61 | 58.90 | a | 62.65 | 63.81 | 50.83 | 39.37 | a | 27.21 | a | 18.23 | 40.26 | ||||||||||
1944 | 20.16 | 25.55 | 25.65 | 36.80 | 48.90 | a | 57.93 | 61.58 | 60.97 | 51.67 | 43.19 | 31.27 | 22.90 | 40.55 | ||||||||||||
1945 | 23.07 | a | 25.93 | 31.77 | 33.76 | a | 46.68 | 53.57 | 60.45 | 62.48 | 51.67 | 42.76 | b | 30.87 | 18.90 | 40.16 | ||||||||||
1946 | 17.97 | 23.43 | 31.77 | 44.37 | 45.45 | 57.27 | 62.65 | 61.87 | 55.93 | 40.39 | 29.47 | 26.55 | 41.43 | |||||||||||||
1947 | 19.45 | 19.50 | 26.71 | 37.17 | 48.68 | 55.97 | 62.58 | 62.87 | 55.23 | 45.87 | 25.60 | 25.00 | 40.39 | |||||||||||||
1948 | 18.61 | 23.37 | b | 23.16 | 41.37 | 49.44 | d | 57.50 | 60.94 | 60.19 | 52.00 | 39.10 | 26.52 | a | 22.52 | 39.56 | ||||||||||
1949 | 15.58 | 24.82 | 31.58 | 38.97 | 48.83 | a | 57.30 | 62.77 | 59.13 | 51.83 | 40.03 | 33.73 | 20.71 | 40.44 | ||||||||||||
1950 | 22.58 | 24.93 | 25.13 | 35.90 | 45.23 | 57.17 | 60.06 | 56.55 | 53.07 | 46.73 | a | 28.10 | a | 23.71 | 39.93 | |||||||||||
1951 | 19.16 | 24.85 | a | 27.94 | 37.40 | 50.71 | 56.00 | 65.03 | 62.48 | 50.67 | 41.00 | 25.77 | 21.61 | 40.22 | ||||||||||||
1952 | 24.71 | 25.00 | 26.60 | a | 38.43 | 48.23 | 63.70 | 62.71 | 64.39 | 52.57 | 39.61 | 25.67 | 21.32 | 41.08 | ||||||||||||
1953 | 27.39 | 21.14 | 33.90 | 35.55 | a | 44.71 | 65.20 | 64.48 | 61.26 | 53.17 | 44.55 | 33.24 | a | 21.61 | 42.18 | |||||||||||
1954 | 24.55 | 31.56 | a | 28.03 | 44.23 | 48.23 | a | 60.03 | 65.16 | 62.55 | 57.13 | 44.87 | 31.97 | 26.71 | 43.75 | |||||||||||
1955 | 19.87 | 18.46 | 29.27 | a | 40.13 | 49.87 | 54.10 | 63.48 | 61.97 | 54.73 | 43.97 | 27.10 | 25.90 | a | 40.74 | |||||||||||
1956 | 23.06 | 20.54 | a | 28.13 | 36.50 | 51.26 | 61.03 | a | 62.97 | 61.42 | 54.63 | 43.77 | 27.70 | 23.84 | 41.24 | |||||||||||
1957 | 21.10 | 30.79 | 32.31 | b | 38.50 | 48.39 | 55.80 | 65.10 | 62.19 | 50.97 | 44.48 | 29.97 | 26.33 | a | 42.16 | |||||||||||
1958 | 22.84 | 26.46 | 27.35 | 37.33 | 52.71 | 59.50 | 62.00 | 62.13 | 55.73 | 43.35 | 29.50 | 24.13 | 41.92 | |||||||||||||
1959 | 17.77 | 24.18 | 27.16 | 37.30 | 49.06 | 58.63 | 59.84 | 61.94 | 50.93 | a | 39.35 | 25.90 | 28.00 | 40.01 | ||||||||||||
1960 | 20.32 | 19.89 | a | 28.03 | 37.73 | 44.61 | 57.23 | 61.07 | a | 60.29 | 53.60 | 41.52 | 31.23 | 23.39 | 39.91 | |||||||||||
1961 | 18.97 | 24.39 | 30.39 | 35.20 | 45.71 | 58.07 | 59.45 | 60.77 | 50.10 | 39.87 | a | 27.60 | 21.90 | 39.37 | ||||||||||||
1962 | 16.84 | 27.93 | 25.55 | 39.53 | 47.48 | 54.13 | 61.32 | 59.65 | 53.57 | 44.87 | 31.86 | a | 24.65 | 40.61 | ||||||||||||
1963 | 9.90 | 26.39 | 29.03 | 41.93 | 51.00 | 57.67 | 64.58 | 62.94 | 56.90 | 47.06 | 31.57 | 18.10 | 41.42 | |||||||||||||
1964 | 21.10 | 19.41 | 24.55 | 37.30 | 50.19 | 56.33 | 64.57 | a | 61.97 | 54.67 | 42.65 | 32.37 | 21.81 | 40.58 | ||||||||||||
1965 | 24.65 | 19.50 | 23.00 | 39.43 | 48.37 | a | 55.90 | 63.19 | 59.10 | a | 52.17 | 39.84 | 34.77 | 25.97 | 40.49 | |||||||||||
1966 | 15.84 | 19.43 | 27.74 | 36.73 | 47.74 | 57.67 | 64.55 | 58.48 | 53.20 | 39.33 | a | 31.23 | 17.94 | 39.16 | ||||||||||||
1967 | 22.45 | 23.14 | 31.58 | 41.27 | 44.53 | a | 57.48 | a | 61.42 | 56.58 | 50.97 | 38.13 | a | 26.13 | 19.35 | 39.42 | ||||||||||
1968 | 21.87 | 21.76 | 29.13 | 35.07 | a | 46.10 | 56.83 | a | 60.35 | 60.45 | 50.90 | 43.03 | 30.30 | 18.29 | 39.51 | |||||||||||
1969 | 23.77 | 24.25 | 22.58 | 40.43 | 48.87 | 55.80 | 63.45 | 62.29 | 55.20 | 39.26 | 27.40 | 23.16 | 40.54 | |||||||||||||
1970 | 16.23 | 23.07 | 22.39 | 33.30 | 46.58 | 51.73 | 61.58 | 59.10 | b | 51.77 | 36.03 | 25.60 | 20.06 | 37.29 | ||||||||||||
1971 | 16.90 | 20.00 | 25.87 | a | 34.00 | 42.23 | 55.13 | 60.19 | 57.03 | 48.33 | 39.65 | 29.63 | 24.10 | b | 37.76 | |||||||||||
1972 | 18.23 | 19.92 | c | 31.39 | 37.07 | b | 46.61 | 55.07 | 57.90 | 56.77 | 51.93 | 40.77 | 22.37 | 20.26 | 38.19 | |||||||||||
1973 | 20.10 | 24.68 | 30.08 | e | 33.50 | f | 44.90 | 53.00 | 59.84 | 58.48 | 50.77 | 41.42 | 30.50 | 21.32 | 39.55 | a | ||||||||||
1974 | 17.97 | 22.32 | 31.81 | 37.80 | 50.19 | 55.53 | 62.00 | 56.29 | 46.90 | 42.26 | 27.23 | 16.90 | 38.93 | |||||||||||||
1975 | 17.06 | 20.32 | 27.16 | 34.10 | 43.13 | 53.50 | 58.45 | 59.71 | 49.73 | 38.97 | 26.67 | 22.52 | 37.61 | |||||||||||||
1976 | 17.29 | 26.90 | 27.26 | 38.17 | 44.17 | a | 54.73 | 60.29 | 58.29 | 51.27 | 35.61 | 23.57 | 19.29 | 38.07 | ||||||||||||
1977 | 14.39 | 23.50 | 26.71 | 39.57 | 49.39 | 57.97 | 62.55 | 61.58 | 52.79 | a | 41.77 | 29.10 | 24.71 | 40.34 | ||||||||||||
1978 | 15.71 | 18.25 | 30.10 | 39.67 | 45.48 | 58.67 | 62.71 | 57.94 | 52.27 | 40.26 | 32.77 | 17.77 | 39.30 | |||||||||||||
1979 | 13.65 | 23.00 | 31.45 | 38.30 | 46.65 | 54.00 | 60.81 | 57.84 | 51.30 | 40.90 | 25.33 | 21.84 | 38.76 | |||||||||||||
1980 | 20.84 | 23.76 | 27.13 | 32.73 | 45.77 | 56.83 | 65.65 | 61.00 | 54.67 | 37.52 | 28.93 | 28.48 | 40.28 | |||||||||||||
1981 | 23.03 | 22.46 | 32.65 | 43.87 | 48.00 | 60.60 | 64.30 | a | 60.06 | 53.13 | 43.06 | 33.77 | 22.23 | 42.26 | ||||||||||||
1982 | 22.19 | 19.79 | 29.65 | 36.77 | 47.97 | 54.70 | 61.29 | 61.71 | 53.66 | a | 39.10 | 29.23 | 22.71 | 39.90 | ||||||||||||
1983 | 22.37 | a | 24.54 | 31.55 | 33.17 | 41.52 | 52.43 | 60.58 | 62.03 | 54.50 | 43.45 | 31.60 | 13.39 | 39.26 | ||||||||||||
1984 | 18.77 | 22.79 | 26.52 | 34.33 | 47.94 | 56.93 | 61.10 | 60.87 | 50.80 | 39.90 | 30.33 | 25.83 | a | 39.68 | ||||||||||||
1985 | 18.70 | a | 21.46 | 32.40 | a | 39.40 | 48.68 | 55.80 | 59.74 | 60.23 | 51.87 | 40.87 | 28.53 | 19.13 | 39.73 | |||||||||||
1986 | 25.10 | 25.04 | 34.45 | 40.13 | 45.55 | b | 57.73 | 62.61 | 60.00 | 53.73 | 41.97 | a | 28.83 | 23.87 | 41.58 | |||||||||||
1987 | 20.00 | 27.93 | 27.71 | 36.07 | 47.65 | 56.77 | 62.71 | q | 60.03 | a | 51.54 | b | 40.40 | a | 28.47 | 18.97 | 37.77 | a | ||||||||
1988 | 15.42 | 19.38 | 26.23 | 36.20 | 45.79 | b | 56.97 | 59.68 | 61.23 | e | 50.90 | 41.31 | b | 28.83 | a | 18.86 | c | 38.40 | ||||||||
1989 | 21.00 | 17.28 | c | 30.42 | 39.43 | 50.21 | b | 54.43 | 59.86 | c | 59.81 | e | 49.54 | b | 38.63 | a | 26.97 | 12.17 | g | 40.69 | a | |||||
1990 | 18.90 | 22.67 | a | 29.42 | 38.30 | c | 44.53 | a | 59.55 | a | 61.23 | a | 59.64 | f | 55.48 | g | 39.61 | c | 30.83 | a | 12.62 | e | 35.77 | b | ||
1991 | 18.18 | c | 25.36 | 29.17 | b | 37.83 | a | 46.32 | c | 57.39 | b | 61.00 | ----- | z | 46.95 | k | 39.58 | l | 24.25 | b | 22.68 | 35.80 | c | |||
1992 | 21.81 | 25.25 | a | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 20.10 | 22.38 | i | ||
1993 | 17.81 | 19.68 | 28.65 | 35.90 | a | 48.45 | 56.53 | 62.84 | 60.77 | 49.14 | a | 35.58 | 22.90 | ----- | z | 39.84 | a | |||||||||
1994 | 16.52 | 18.57 | 29.72 | b | 37.07 | a | 49.87 | 60.30 | 60.97 | 62.10 | 51.60 | 40.19 | 29.83 | 24.45 | 40.10 | |||||||||||
1995 | 21.97 | 26.64 | 31.13 | 34.90 | 45.28 | b | 55.33 | 59.39 | 62.97 | 53.17 | 36.10 | 29.63 | 22.48 | 39.92 | ||||||||||||
1996 | 17.39 | 24.54 | a | 25.20 | a | 36.20 | 50.94 | 57.53 | 61.13 | 59.13 | 48.63 | 36.27 | a | 25.00 | b | 17.16 | 38.26 | |||||||||
1997 | 17.03 | 20.54 | 28.74 | 31.66 | a | 46.71 | 57.03 | 61.94 | 61.59 | b | 55.43 | 40.42 | 26.47 | 20.32 | 38.99 | |||||||||||
1998 | 21.97 | 25.74 | a | 27.71 | 33.79 | b | 47.40 | a | 56.27 | 64.00 | w | ----- | z | 55.80 | 43.29 | 31.93 | 19.52 | 36.34 | b | |||||||
1999 | 22.42 | 25.64 | 30.03 | 35.59 | a | 45.94 | 55.29 | b | 63.61 | 61.55 | 52.28 | a | 37.74 | 31.07 | 21.07 | a | 40.18 | |||||||||
2000 | 21.39 | 26.34 | 32.81 | 38.67 | 50.40 | a | 58.93 | a | 62.87 | 63.65 | 53.13 | 43.39 | 25.10 | a | 18.74 | 41.28 | ||||||||||
2001 | 19.77 | 24.79 | 30.94 | 39.30 | 48.90 | 57.93 | 65.94 | 61.42 | 52.57 | 38.71 | 35.77 | 21.94 | 41.50 | |||||||||||||
2002 | 21.48 | 21.15 | a | 23.63 | a | 42.03 | 47.32 | 62.93 | a | 63.87 | 62.06 | 54.60 | 39.90 | 29.93 | 20.45 | 40.78 | ||||||||||
2003 | 23.61 | 21.89 | 31.10 | 38.17 | 49.42 | 54.83 | 64.62 | b | 63.17 | a | 52.10 | 42.52 | 28.86 | a | 21.84 | 41.01 | ||||||||||
2004 | 20.19 | 20.14 | a | 35.23 | 39.62 | a | 48.96 | f | 57.33 | 61.23 | 58.10 | 52.66 | a | 39.79 | g | 29.67 | 21.70 | a | 39.59 | b | ||||||
2005 | 24.87 | 26.89 | 26.75 | c | 37.33 | 48.27 | a | 54.93 | a | 60.55 | 59.97 | 53.83 | 40.29 | 27.30 | 16.87 | 39.82 | ||||||||||
2006 | 20.94 | 17.21 | 31.61 | m | 39.28 | a | 50.19 | 60.17 | 63.30 | a | 61.83 | a | 47.93 | b | 38.77 | 27.83 | 21.65 | 40.83 | a | |||||||
2007 | 15.68 | 19.81 | a | 32.58 | 35.13 | 47.21 | b | 54.67 | c | 60.90 | 62.90 | a | 53.89 | b | 39.06 | 27.54 | b | 20.48 | 39.15 | |||||||
2008 | 17.55 | b | 20.89 | a | 28.16 | 33.70 | 45.93 | a | 58.54 | b | 63.23 | 60.94 | 51.63 | c | 41.13 | 31.07 | 18.83 | b | 39.30 | |||||||
2009 | 21.13 | 27.32 | f | 30.48 | 36.27 | 48.33 | a | 56.52 | a | 62.30 | a | 59.55 | b | 50.77 | h | 36.65 | k | 31.15 | c | 16.38 | e | 40.23 | c | |||
2010 | 16.14 | b | 15.41 | a | 29.27 | a | 38.96 | g | 44.23 | a | 60.79 | a | 63.60 | a | 59.74 | 55.13 | 40.19 | 24.62 | a | 24.50 | c | 39.42 | a | |||
2011 | 15.48 | b | 21.84 | c | 30.03 | b | 36.87 | 43.60 | a | 58.61 | b | 65.55 | 64.83 | b | 51.17 | 39.43 | a | 28.70 | 18.66 | b | 39.56 | |||||
2012 | 22.43 | a | ----- | z | 33.77 | a | 42.17 | 50.19 | 60.10 | 64.74 | 60.23 | a | 51.10 | a | 37.61 | ----- | z | ----- | z | 46.93 | c | |||||
2013 | 18.58 | 21.25 | ----- | z | 31.13 | 46.48 | 60.57 | 63.32 | 62.06 | 57.10 | 37.13 | 27.80 | 19.77 | 40.47 | a | |||||||||||
2014 | 17.48 | 19.75 | 25.74 | 35.70 | 46.32 | 57.77 | 62.65 | 60.26 | 54.53 | 42.00 | 25.33 | 21.29 | 39.07 | |||||||||||||
2015 | 19.97 | 23.29 | 30.03 | 36.10 | 46.20 | a | 58.77 | 62.94 | 60.39 | 57.20 | 45.32 | 28.03 | 20.61 | 40.74 | ||||||||||||
2016 | 18.87 | 22.72 | 28.39 | 35.13 | 42.61 | 58.13 | 61.86 | b | 58.90 | 53.03 | 40.97 | a | 31.80 | 16.90 | 39.11 | |||||||||||
2017 | 20.52 | 26.14 | 30.87 | 36.23 | 43.58 | 57.13 | 62.87 | 58.71 | 52.10 | 39.48 | 32.93 | 18.27 | a | 39.90 | ||||||||||||
2018 | 15.94 | 19.75 | 29.10 | 33.40 | 50.45 | 59.63 | 61.90 | 60.03 | 52.33 | 41.61 | 25.07 | 18.84 | 39.00 | |||||||||||||
2019 | 20.81 | 18.21 | 26.42 | 36.13 | 41.65 | 53.07 | a | 60.73 | a | 59.03 | a | 55.43 | 32.61 | 23.70 | 21.74 | 37.46 | ||||||||||
2020 | 21.97 | 21.28 | 33.10 | 34.40 | 48.40 | a | 51.37 | 57.23 | 56.61 | 41.97 | 30.39 | 32.33 | 21.06 | 37.51 | ||||||||||||
2021 | 21.03 | 14.57 | 29.61 | 34.93 | 45.42 | 52.53 | 61.77 | 61.19 | 53.80 | 35.48 | 27.57 | 25.84 | 38.65 | |||||||||||||
2022 | 16.52 | 15.25 | 26.06 | 35.00 | 47.26 | 60.60 | 65.94 | 62.03 | 55.67 | 38.43 | a | ----- | z | 16.16 | 39.90 | a | ||||||||||
2023 | 19.45 | 18.32 | 27.81 | 34.57 | 50.81 | 57.10 | 61.04 | e | 62.07 | b | 54.57 | b | 41.20 | a | 28.43 | 25.45 | k | 41.40 | a | |||||||
Period of Record Statistics | ||||||||||||||||||||||||||
MEAN | 19.73 | 22.62 | 29.10 | 37.47 | 47.50 | 57.24 | 62.27 | 60.87 | 52.72 | 40.72 | 28.85 | 21.62 | 40.04 | |||||||||||||
S.D. | 3.21 | 3.42 | 2.99 | 2.81 | 2.57 | 2.59 | 1.96 | 2.13 | 2.51 | 3.06 | 2.86 | 3.22 | 1.34 | |||||||||||||
SKEW | -0.22 | 0.05 | -0.06 | 0.22 | -0.16 | 0.24 | 0.01 | 0.06 | -0.91 | -0.36 | 0.06 | -0.21 | 0.13 | |||||||||||||
MAX | 27.39 | 31.56 | 35.68 | 44.37 | 52.71 | 65.20 | 66.34 | 67.00 | 57.20 | 47.07 | 35.77 | 28.48 | 43.75 | |||||||||||||
MIN | 9.90 | 14.57 | 22.39 | 31.13 | 41.52 | 51.37 | 57.23 | 56.29 | 41.97 | 30.39 | 22.37 | 12.62 | 37.29 | |||||||||||||
YRS | 88 | 87 | 85 | 86 | 87 | 88 | 86 | 86 | 84 | 85 | 87 | 86 | 69 |