YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
1926 | ----- | z | ----- | z | ----- | z | 34.17 | r | 35.52 | 41.90 | 46.26 | 45.32 | 41.57 | 30.90 | 21.80 | 11.87 | a | 34.39 | d | |||||||
1927 | 19.94 | 22.04 | 17.70 | a | 30.63 | 33.16 | 41.14 | a | 52.35 | 53.42 | 40.14 | a | 26.06 | 18.63 | 9.52 | 30.39 | ||||||||||
1928 | 10.23 | 14.21 | 21.39 | 24.13 | 38.84 | 42.43 | 50.71 | 45.65 | 33.90 | 23.61 | 14.77 | 9.10 | a | 27.41 | ||||||||||||
1929 | 5.58 | 10.61 | 21.97 | 23.33 | 33.29 | 42.70 | 52.32 | 48.39 | 39.63 | 28.87 | 12.41 | a | 9.52 | 27.39 | ||||||||||||
1930 | 10.32 | 18.79 | 18.13 | 26.10 | 30.00 | 41.13 | 50.62 | e | 47.06 | 36.60 | 25.23 | ----- | z | ----- | z | 30.40 | b | |||||||||
1931 | 6.94 | 20.57 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 13.75 | j | ||
1932 | ----- | z | ----- | z | ----- | z | ----- | z | 33.71 | g | 37.47 | 49.48 | 46.84 | 33.87 | 26.74 | 12.90 | -3.71 | 29.08 | e | |||||||
1933 | 5.52 | 5.93 | ----- | z | ----- | z | ----- | z | ----- | z | 50.91 | t | 46.74 | ----- | z | ----- | z | 14.20 | t | 14.55 | 18.18 | h | ||||
1934 | -0.61 | c | 6.50 | ----- | z | ----- | z | 41.19 | 36.30 | 48.68 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 26.41 | g | ||||
1935 | ----- | z | 7.57 | 17.16 | 28.43 | 37.48 | ----- | z | 51.90 | ----- | z | ----- | z | ----- | z | ----- | z | 1.33 | s | 28.51 | g | |||||
1936 | 0.80 | a | 15.69 | 15.81 | 27.57 | 35.00 | 43.63 | 53.94 | 53.65 | 41.57 | 24.58 | 11.37 | 7.42 | 27.58 | ||||||||||||
1937 | 0.00 | b | 13.00 | 16.48 | 24.20 | 31.87 | 41.38 | a | 49.93 | a | 43.97 | 37.47 | 26.58 | 12.10 | 10.26 | 25.60 | ||||||||||
1938 | 9.25 | c | 10.64 | 16.81 | 22.23 | 33.77 | 40.97 | 50.74 | 46.32 | 43.73 | 30.06 | 7.23 | 12.86 | b | 27.05 | |||||||||||
1939 | 9.39 | 9.25 | 21.81 | 27.17 | 33.13 | 42.00 | 52.32 | c | 50.17 | a | 46.47 | 29.55 | 19.85 | c | 18.74 | 29.99 | ||||||||||
1940 | 17.10 | 19.90 | 25.00 | 29.47 | 37.94 | 47.17 | 50.97 | 48.45 | 43.57 | 32.32 | 21.13 | 19.48 | 32.71 | |||||||||||||
1941 | 19.00 | 23.25 | 20.39 | 26.50 | 37.19 | 43.13 | 49.52 | 47.71 | 41.53 | 31.61 | 18.83 | 18.94 | 31.47 | |||||||||||||
1942 | 17.52 | 12.82 | 16.13 | 29.00 | 32.65 | 39.93 | 49.94 | 48.50 | a | 41.40 | 31.06 | 24.47 | 21.19 | 30.38 | ||||||||||||
1943 | 18.97 | 20.86 | 23.90 | 30.77 | 36.10 | a | 46.40 | 51.42 | g | 50.94 | 44.60 | 29.58 | 19.80 | 15.46 | g | 32.19 | b | |||||||||
1944 | 10.97 | ----- | z | ----- | z | ----- | z | 38.38 | r | ----- | z | ----- | z | ----- | z | ----- | z | 37.81 | 24.20 | 17.77 | a | 22.69 | h | |||
1945 | 16.60 | a | 22.86 | 22.55 | 27.17 | 38.94 | 45.00 | 53.45 | 53.97 | 43.60 | 35.00 | 20.57 | 13.39 | 32.76 | ||||||||||||
1946 | 10.32 | 17.14 | 25.42 | 34.40 | y | 36.74 | 47.53 | m | 52.76 | j | 52.39 | 47.52 | a | 31.93 | d | 19.57 | b | 17.94 | 28.77 | c | ||||||
1947 | 9.83 | a | 19.35 | k | 22.04 | e | 29.07 | 39.84 | 45.71 | b | 53.74 | l | 52.27 | a | 44.52 | a | 33.00 | 18.57 | 12.50 | c | 30.73 | b | ||||
1948 | 13.61 | 17.33 | h | 21.56 | d | 33.35 | d | 37.48 | 47.77 | 52.90 | a | 51.55 | 45.45 | a | 32.47 | a | 18.57 | 22.40 | a | 34.28 | a | |||||
1949 | 13.48 | b | 17.39 | 23.53 | a | 29.83 | 38.97 | 46.43 | b | 54.52 | b | 50.97 | 46.27 | 33.68 | f | 23.47 | 12.48 | b | 32.49 | a | ||||||
1950 | 16.18 | c | 21.12 | b | 24.55 | 31.23 | 36.70 | d | 47.04 | c | 53.90 | a | 47.65 | 41.41 | a | 32.33 | y | 22.83 | 19.52 | d | 32.92 | a | ||||
1951 | 15.87 | 19.22 | a | 22.74 | 29.17 | 38.20 | a | 43.23 | 56.00 | 53.72 | b | 44.07 | b | 33.83 | b | 22.39 | b | 19.00 | 33.12 | |||||||
1952 | 20.07 | a | 18.43 | a | 19.65 | 30.27 | 39.13 | 47.87 | 49.83 | a | ----- | z | ----- | z | 23.56 | f | 17.37 | k | 10.43 | a | 29.46 | d | ||||
1953 | 16.13 | 9.18 | 23.42 | 26.50 | 28.61 | 42.63 | 50.23 | 46.58 | 35.93 | 24.70 | a | 14.20 | 8.92 | g | 28.92 | a | ||||||||||
1954 | 16.00 | f | 13.89 | 21.35 | 28.03 | 34.74 | 38.77 | 49.26 | 46.39 | 41.07 | 33.00 | 15.83 | ----- | z | 32.23 | b | ||||||||||
1955 | 12.37 | a | 8.30 | a | 18.77 | 22.10 | 34.23 | 39.83 | 48.52 | 48.77 | 34.10 | 29.48 | 19.13 | 16.03 | 27.64 | |||||||||||
1956 | 15.90 | 9.18 | a | 17.32 | 22.77 | 29.81 | 43.03 | 45.45 | 40.13 | 35.03 | 23.84 | 4.90 | 1.23 | 24.05 | ||||||||||||
1957 | 13.74 | 19.89 | 20.13 | 23.67 | 33.23 | 43.03 | 49.48 | 46.42 | 32.97 | 28.71 | 13.97 | 13.97 | 28.27 | |||||||||||||
1958 | 13.58 | 20.82 | 21.04 | g | 26.70 | 36.58 | 46.23 | 50.16 | 49.71 | 43.40 | 31.81 | 18.27 | 14.03 | 31.94 | a | |||||||||||
1959 | 13.87 | 14.68 | 14.77 | 27.53 | 31.77 | 43.47 | 49.61 | 49.65 | 37.43 | 25.31 | e | 11.00 | g | 10.76 | j | 30.81 | b | |||||||||
1960 | 7.39 | 16.11 | a | 18.45 | b | 23.04 | c | 29.06 | 42.90 | t | 48.13 | a | 46.00 | i | 40.79 | a | 29.00 | a | 15.03 | 10.58 | e | 23.76 | b | |||
1961 | 8.14 | c | 15.36 | 20.89 | c | ----- | z | 35.48 | h | 43.83 | x | 47.54 | c | 47.16 | l | 37.17 | g | 22.74 | l | 18.25 | n | 10.93 | c | 20.57 | g | |
1962 | 14.27 | a | 18.19 | g | 11.52 | j | 24.00 | k | ----- | z | 35.75 | n | 50.06 | n | 44.38 | o | 43.54 | q | 26.39 | m | 20.64 | h | 12.47 | l | 14.27 | k |
1963 | 8.46 | c | 11.96 | a | 15.10 | k | 27.21 | f | 32.05 | i | 36.41 | h | 50.00 | f | 50.10 | k | 42.38 | f | 28.40 | f | 16.60 | j | 4.36 | f | 10.21 | j |
1964 | 0.26 | d | 1.80 | n | 12.74 | l | 19.92 | r | 30.85 | k | 38.68 | b | 52.04 | c | 46.29 | n | 42.46 | d | 25.56 | d | 13.29 | i | 10.88 | e | 28.31 | f |
1965 | 14.03 | b | 10.14 | 16.03 | ----- | z | 32.35 | 39.88 | f | 52.79 | l | 47.06 | 41.53 | 23.27 | e | 19.87 | 14.55 | 24.32 | c | |||||||
1966 | 5.38 | b | 15.12 | d | 18.32 | 26.57 | 35.13 | 44.13 | 54.10 | 48.67 | a | 40.41 | c | 27.87 | 18.69 | d | 7.93 | c | 28.53 | |||||||
1967 | 7.16 | 14.92 | c | 20.84 | 25.56 | e | 30.96 | c | 43.47 | 52.68 | 46.94 | 42.63 | 27.32 | 20.33 | 10.90 | 28.64 | ||||||||||
1968 | 11.42 | 21.56 | d | 19.55 | b | 23.61 | b | 31.48 | 41.72 | a | 51.23 | a | 47.33 | d | 34.78 | c | 26.55 | 19.60 | 2.00 | u | 29.89 | a | ||||
1969 | 16.69 | b | 14.04 | a | 14.83 | a | 24.93 | c | 33.87 | a | 39.45 | h | 51.83 | g | 50.33 | j | 42.52 | g | 30.84 | f | 16.08 | f | 14.92 | f | 20.87 | g |
1970 | 7.17 | a | ----- | z | 17.72 | f | 19.64 | b | 31.40 | f | 40.30 | g | 51.70 | d | 49.47 | a | 39.58 | k | 25.77 | i | ----- | z | ----- | z | 31.99 | h |
1971 | 8.06 | 14.96 | b | 19.77 | 21.57 | 30.23 | 41.43 | 51.97 | 48.87 | 39.45 | a | 28.24 | f | 19.24 | a | 11.39 | h | 29.56 | b | |||||||
1972 | 12.44 | f | 13.11 | b | 21.40 | a | 22.07 | c | 29.19 | 41.00 | s | 50.97 | b | 48.14 | c | 41.76 | a | 35.46 | c | 18.62 | d | 9.59 | n | 31.19 | c | |
1973 | ----- | z | 17.50 | 19.97 | a | 22.37 | 33.72 | b | 38.56 | e | 46.72 | f | 40.64 | t | 35.54 | f | 22.65 | e | 13.70 | j | 5.09 | i | 25.80 | f | ||
1974 | 9.48 | j | 6.57 | g | 19.48 | j | 20.18 | m | 31.47 | p | 48.00 | v | 49.55 | b | 45.46 | c | 37.50 | f | 33.76 | b | 16.19 | d | 4.00 | c | 29.79 | g |
1975 | 9.89 | l | 10.14 | n | 17.00 | m | 22.09 | s | 27.53 | l | ----- | z | 48.67 | p | ----- | z | 37.91 | s | 21.43 | q | 10.64 | p | 11.55 | t | ----- | z |
1976 | 3.00 | p | ----- | z | ----- | z | 25.17 | x | 31.91 | t | 37.00 | q | 47.50 | o | 43.67 | p | 36.30 | t | 25.08 | r | -0.20 | y | 6.06 | n | ----- | z |
1977 | 8.30 | u | 13.09 | q | 10.77 | r | 27.83 | r | 32.40 | f | 44.24 | i | 51.55 | k | 50.15 | d | 43.38 | i | 30.35 | e | ----- | z | 17.53 | l | 40.25 | j |
1978 | 17.25 | g | ----- | z | 21.70 | u | 25.50 | f | 33.63 | l | 46.31 | q | 51.55 | b | 47.87 | 41.21 | a | 30.06 | 25.88 | e | 15.43 | a | 35.33 | f | ||
1979 | 14.94 | 19.63 | a | 21.61 | 26.21 | b | 36.77 | 43.60 | 50.45 | 46.52 | 43.00 | 30.24 | b | 17.83 | 10.00 | c | 30.07 | |||||||||
1980 | 22.14 | b | 19.69 | 20.00 | a | 23.41 | a | 31.57 | a | 41.04 | d | 51.74 | 51.23 | a | 43.27 | 22.80 | a | 13.56 | c | 14.07 | d | 29.54 | ||||
1981 | 15.48 | f | 14.74 | e | 22.67 | a | 30.15 | d | 39.17 | a | 49.07 | c | 52.00 | c | 48.93 | a | 41.18 | b | 34.32 | 20.59 | a | 14.97 | 33.44 | a | ||
1982 | 16.38 | b | 20.04 | 23.86 | b | 29.93 | b | 33.17 | a | 39.32 | b | 50.84 | 51.90 | b | 44.10 | a | 23.06 | 23.04 | b | 16.52 | b | 31.01 | ||||
1983 | 13.93 | a | 20.04 | a | 23.20 | a | 21.27 | h | 31.93 | d | 42.10 | a | 50.13 | a | 50.94 | 47.31 | a | 34.79 | b | 23.90 | 22.55 | 32.80 | a | |||
1984 | 15.50 | a | 13.00 | a | 19.45 | 18.38 | d | 38.83 | a | 46.18 | b | 50.00 | a | 50.10 | a | 43.47 | 31.37 | d | 17.27 | 16.90 | a | 30.04 | ||||
1985 | 17.48 | 17.54 | 23.63 | a | 28.76 | a | 37.32 | 44.20 | 49.68 | c | 48.66 | b | 39.33 | c | 30.38 | e | 23.41 | c | 13.21 | b | 31.13 | |||||
1986 | 11.10 | a | 16.86 | 20.23 | 28.77 | 36.00 | 47.77 | 49.63 | a | 51.42 | 38.13 | 27.87 | 22.52 | a | 15.27 | a | 30.46 | |||||||||
1987 | 12.10 | a | 18.39 | 17.38 | b | 24.93 | 32.71 | 40.50 | 47.10 | 46.48 | 37.47 | 29.74 | 15.55 | a | 9.52 | d | 27.66 | |||||||||
1988 | 7.09 | t | 20.93 | 19.11 | c | 27.56 | c | 36.36 | c | 47.63 | c | 53.19 | e | 53.17 | a | 38.87 | 32.13 | a | 22.79 | b | 10.62 | b | 32.94 | a | ||
1989 | 11.16 | 20.96 | 21.84 | 35.03 | 39.40 | k | 43.88 | f | 54.96 | e | 49.67 | g | ----- | z | 30.10 | a | 20.33 | 10.90 | a | 25.66 | d | |||||
1990 | 7.68 | 17.41 | a | 24.00 | b | 32.86 | a | 37.90 | a | 47.85 | c | 54.17 | a | 47.90 | b | 48.48 | c | 27.56 | d | 21.32 | b | 10.48 | 31.47 | |||
1991 | 18.26 | 18.61 | 27.83 | s | ----- | z | 39.45 | t | ----- | z | 52.87 | a | 53.00 | 45.33 | 29.97 | 22.77 | 16.67 | a | 32.18 | d | ||||||
1992 | 6.80 | a | 24.34 | 24.65 | 32.62 | a | 42.29 | 45.07 | 51.42 | 50.00 | 42.33 | 32.74 | 17.14 | a | 11.00 | b | 31.70 | |||||||||
1993 | 24.19 | 22.00 | 22.58 | 27.83 | a | 37.94 | 45.03 | 54.45 | 53.06 | 39.70 | 30.13 | 19.86 | a | 11.50 | a | 32.36 | ||||||||||
1994 | 10.93 | a | 15.46 | 22.57 | a | 29.93 | a | 38.23 | 50.83 | 54.39 | 54.10 | 46.03 | 32.93 | a | 24.93 | c | 21.20 | a | 33.46 | |||||||
1995 | 21.55 | 22.86 | f | 25.35 | 28.03 | a | 37.97 | 46.93 | a | 52.35 | 56.23 | 47.37 | 31.48 | 26.14 | a | 16.93 | a | 35.49 | a | |||||||
1996 | 18.32 | 28.03 | 22.74 | 31.70 | 43.00 | 52.77 | 57.97 | 55.52 | 46.00 | 35.63 | a | 23.24 | a | 20.07 | a | 36.25 | ||||||||||
1997 | 20.03 | a | 18.46 | 21.84 | 30.97 | 39.86 | b | 45.50 | 52.26 | 53.90 | 49.63 | 30.55 | 23.27 | 9.97 | b | 33.02 | ||||||||||
1998 | 20.32 | 20.18 | 24.30 | a | 24.87 | 35.84 | 45.90 | 55.82 | c | 51.97 | 47.10 | 34.87 | 23.90 | a | 16.21 | c | 33.44 | |||||||||
1999 | 18.52 | 16.23 | b | 24.97 | 28.30 | 37.90 | a | 46.76 | a | 56.61 | 52.90 | 46.43 | 28.27 | a | 17.83 | a | 9.87 | a | 32.05 | |||||||
2000 | 15.65 | 18.62 | 21.32 | 33.07 | b | ----- | z | ----- | z | 56.19 | 53.90 | 45.52 | a | 37.33 | a | 20.00 | a | 16.19 | d | 31.78 | b | |||||
2001 | 14.15 | d | 20.57 | 23.50 | a | 32.43 | 41.90 | a | 48.93 | a | 54.42 | 52.39 | 43.93 | 34.17 | a | 24.86 | b | 12.21 | b | 33.62 | ||||||
2002 | 16.93 | b | 15.46 | 18.40 | a | 33.83 | 35.68 | 50.00 | 54.84 | 51.48 | 45.17 | 31.13 | 22.14 | b | 15.76 | b | 32.57 | |||||||||
2003 | 19.74 | 21.64 | 22.13 | 28.31 | a | 38.81 | 48.60 | 56.60 | a | 54.10 | 45.27 | 38.13 | 23.59 | a | 14.41 | b | 34.28 | |||||||||
2004 | 16.68 | 15.72 | 28.61 | 31.72 | a | 39.97 | 46.17 | 52.97 | 49.23 | 41.30 | 33.55 | 26.03 | 14.69 | b | 33.05 | |||||||||||
2005 | 22.00 | 27.39 | 26.00 | 28.77 | 39.29 | 45.87 | 54.28 | b | 51.52 | j | 47.23 | 37.03 | 21.79 | a | 17.23 | 33.35 | a | |||||||||
2006 | 14.77 | a | 17.68 | 22.97 | 30.57 | 42.97 | 50.63 | 56.65 | 55.32 | 41.53 | 33.45 | 18.83 | a | 11.52 | b | 33.07 | ||||||||||
2007 | 16.93 | b | 19.75 | 23.45 | 31.07 | 39.75 | c | 49.10 | 54.06 | 54.32 | 47.07 | 29.65 | 21.69 | a | 17.55 | b | 33.70 | |||||||||
2008 | 15.35 | 20.38 | 21.19 | 26.23 | 36.87 | 47.42 | f | ----- | z | 53.71 | 45.33 | 33.42 | 23.27 | 23.60 | a | 29.94 | b | |||||||||
2009 | 14.90 | 15.22 | a | 26.16 | 29.77 | 44.57 | a | 48.07 | 56.97 | 52.71 | 44.33 | 34.06 | 20.43 | b | ----- | z | 35.20 | a | ||||||||
2010 | 14.52 | 21.82 | 22.81 | 31.67 | 38.20 | a | 50.46 | b | 56.83 | a | 53.68 | 47.43 | 36.10 | a | 17.30 | 21.30 | a | 34.34 | ||||||||
2011 | 10.16 | 12.46 | 26.58 | 34.10 | 35.65 | 46.87 | 57.55 | 57.60 | a | 46.13 | 35.33 | d | 24.21 | a | 16.88 | f | 35.15 | a | ||||||||
2012 | 24.10 | 20.10 | 24.03 | a | 32.67 | 41.23 | 51.97 | 57.48 | 55.10 | 46.90 | 32.94 | 19.00 | d | 14.29 | 34.98 | |||||||||||
2013 | 8.06 | 13.36 | c | 25.19 | 32.41 | c | 40.10 | 52.00 | 56.61 | 53.06 | 47.00 | 29.26 | 24.40 | 17.23 | 33.22 | |||||||||||
2014 | 18.48 | 26.25 | 24.87 | 31.17 | 38.58 | 51.78 | c | 57.55 | 52.97 | 51.10 | 37.03 | 24.50 | 21.90 | 36.35 | ||||||||||||
2015 | 20.48 | 24.11 | 28.55 | 31.63 | 38.42 | 51.10 | 54.48 | 53.90 | 48.21 | b | 39.48 | 23.04 | b | 16.26 | 35.81 | |||||||||||
2016 | 18.03 | 18.24 | 27.48 | 31.67 | 38.29 | 51.27 | 57.42 | 50.74 | 46.03 | 37.06 | 28.00 | 21.65 | 35.49 | |||||||||||||
2017 | 22.06 | 24.86 | 25.55 | 31.33 | 36.94 | 50.70 | 55.29 | 51.97 | 46.00 | 34.77 | 27.70 | 15.00 | 35.18 | |||||||||||||
2018 | 13.13 | 23.43 | 25.58 | 32.93 | 40.29 | 50.60 | 55.10 | 51.90 | 46.30 | 36.42 | 20.90 | 17.27 | a | 34.49 | ||||||||||||
2019 | 19.55 | 19.14 | 27.87 | 32.50 | 35.77 | 46.77 | 55.16 | 55.16 | 47.80 | 32.03 | 22.67 | 20.68 | 34.59 | |||||||||||||
2020 | 19.52 | 22.03 | 28.39 | 33.20 | 41.90 | 50.44 | e | 57.10 | 53.74 | 41.93 | 31.61 | 24.43 | 14.39 | 34.89 | ||||||||||||
2021 | 15.13 | 19.14 | 22.07 | a | 33.68 | b | 41.35 | n | 52.18 | b | 55.42 | 53.16 | 47.37 | 31.52 | 20.13 | 19.37 | a | 33.56 | a | |||||||
2022 | 14.39 | 11.57 | 21.32 | 32.57 | 42.65 | e | 52.97 | 55.63 | a | 53.97 | 46.10 | 35.52 | 17.93 | 20.42 | 33.75 | |||||||||||
2023 | 18.35 | 17.57 | 26.23 | 28.17 | 38.90 | 44.87 | 55.87 | 55.35 | 45.53 | 32.65 | 22.87 | 18.45 | 33.73 | |||||||||||||
2024 | 20.03 | 22.83 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 21.43 | j | ||
Period of Record Statistics | ||||||||||||||||||||||||||
MEAN | 13.90 | 17.42 | 21.94 | 28.38 | 36.49 | 45.46 | 52.66 | 50.62 | 42.95 | 31.01 | 20.08 | 14.49 | 31.68 | |||||||||||||
S.D. | 5.55 | 4.76 | 3.30 | 3.79 | 3.67 | 4.10 | 2.97 | 3.32 | 4.07 | 4.01 | 4.31 | 4.95 | 2.95 | |||||||||||||
SKEW | -0.56 | -0.30 | -0.14 | -0.47 | -0.20 | -0.05 | -0.10 | -0.37 | -0.61 | -0.24 | -0.96 | -0.72 | -0.54 | |||||||||||||
MAX | 24.19 | 28.03 | 28.61 | 35.03 | 44.57 | 52.97 | 57.97 | 57.60 | 51.10 | 39.48 | 28.00 | 23.60 | 36.35 | |||||||||||||
MIN | -0.61 | 5.93 | 14.77 | 18.38 | 28.61 | 36.30 | 45.45 | 40.13 | 32.97 | 22.65 | 4.90 | -3.71 | 24.05 | |||||||||||||
YRS | 86 | 85 | 81 | 79 | 80 | 76 | 83 | 82 | 81 | 83 | 81 | 77 | 50 |