| YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
| 1917 | 2.25 | 0.06 | 0.18 | 0.11 | 0.18 | 0.00 | 0.06 | 0.20 | 0.00 | 0.00 | 0.00 | 0.00 | 3.04 | |||||||||||||
| 1918 | 0.05 | 1.22 | 0.75 | 0.00 | 0.00 | 0.00 | 0.00 | z | 0.00 | z | 0.20 | 1.16 | 0.60 | 0.70 | a | 4.68 | ||||||||||
| 1919 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1920 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1921 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1922 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1923 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1924 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1925 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1926 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1927 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1928 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1929 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1930 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1931 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1932 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1933 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1934 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1935 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1936 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1937 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 1938 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | 2.20 | 2.20 | |||
| 1939 | 1.35 | 0.00 | z | 0.98 | 0.12 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | z | 0.00 | 0.37 | 0.40 | 3.22 | |||||||||||
| 1940 | 2.05 | y | 1.59 | 0.49 | 0.07 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.51 | 0.19 | 2.45 | 5.30 | ||||||||||||
| 1941 | 0.79 | 1.84 | 3.94 | w | 2.55 | 0.16 | 0.00 | 0.00 | 0.39 | 0.00 | 1.24 | 0.30 | 1.17 | 8.44 | ||||||||||||
| 1942 | 0.00 | 0.11 | 0.46 | 0.50 | 0.00 | 0.00 | 0.00 | 1.09 | 0.00 | 0.43 | 0.00 | 0.11 | 2.70 | |||||||||||||
| 1943 | 3.88 | 1.81 | 1.85 | 0.61 | 0.00 | 0.00 | 0.00 | 0.00 | 0.60 | 0.15 | 0.29 | 3.62 | 12.81 | |||||||||||||
| 1944 | 0.21 | 5.45 | 0.52 | 0.48 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 2.29 | 0.31 | 9.26 | |||||||||||||
| 1945 | 0.03 | 1.29 | 1.58 | 0.23 | 0.00 | 0.00 | 0.00 | 0.97 | 0.01 | 0.30 | 0.00 | 1.07 | 5.48 | |||||||||||||
| 1946 | 0.00 | 0.76 | 0.95 | 0.40 | 0.02 | 0.00 | 0.13 | 0.00 | 0.00 | 0.07 | 2.06 | 0.84 | 5.23 | |||||||||||||
| 1947 | 0.10 | 0.09 | 0.83 | 0.24 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.04 | 0.06 | 1.79 | 3.16 | |||||||||||||
| 1948 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | 0.00 | 0.00 | 1.56 | 0.00 | 1.13 | 2.69 | |||||||
| 1949 | 2.56 | 0.30 | 0.58 | 0.15 | a | 0.00 | b | 0.00 | 0.00 | 0.00 | 0.00 | 0.03 | 0.35 | 0.18 | 4.15 | |||||||||||
| 1950 | 0.30 | 0.47 | 0.87 | 0.03 | 0.06 | 0.00 | 0.49 | 0.00 | 0.01 | 0.00 | 0.13 | 0.00 | 2.36 | |||||||||||||
| 1951 | 1.18 | 0.20 | 0.10 | 0.92 | 0.51 | 0.00 | 0.02 | 0.00 | a | 0.02 | 0.45 | 0.10 | 1.81 | 5.31 | ||||||||||||
| 1952 | 3.37 | 0.00 | 2.02 | 0.30 | 0.00 | 0.00 | 0.06 | 0.03 | 0.88 | 0.00 | 1.76 | 1.49 | 9.91 | |||||||||||||
| 1953 | 0.09 | 0.21 | 0.35 | 0.03 | 0.07 | 0.00 | 0.04 | 0.17 | 0.00 | 0.00 | 0.21 | 0.10 | 1.27 | |||||||||||||
| 1954 | 2.79 | 0.15 | 0.99 | 0.02 | 0.04 | 0.02 | 0.07 | 0.00 | 0.11 | 0.00 | 2.13 | 0.27 | 6.59 | |||||||||||||
| 1955 | 1.76 | 0.10 | 0.00 | 0.00 | 0.00 | 0.00 | 0.05 | 0.06 | 0.00 | 0.00 | 0.22 | 0.37 | 2.56 | |||||||||||||
| 1956 | 1.91 | 0.02 | 0.00 | 0.79 | 0.00 | 0.00 | 0.33 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 3.05 | |||||||||||||
| 1957 | 2.12 | 0.16 | 0.62 | 0.14 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 1.37 | 0.24 | 0.65 | 5.31 | |||||||||||||
| 1958 | 0.11 | 1.68 | 1.24 | 1.29 | 0.26 | 0.00 | 0.00 | 0.04 | 0.04 | 0.13 | 0.25 | 0.00 | 5.04 | |||||||||||||
| 1959 | 0.41 | 0.84 | 0.00 | 0.01 | 0.00 | 0.00 | 0.02 | 0.00 | 0.08 | 0.04 | 0.21 | 1.22 | 2.83 | |||||||||||||
| 1960 | 0.68 | 0.38 | 0.01 | 0.14 | 0.02 | 0.00 | 0.03 | 0.00 | 0.20 | 0.08 | 0.66 | 0.08 | 2.28 | |||||||||||||
| 1961 | 0.10 | 0.00 | 0.11 | 0.00 | 0.00 | 0.00 | 0.00 | 0.72 | 0.00 | 0.05 | 0.48 | 0.69 | 2.15 | |||||||||||||
| 1962 | 0.31 | 1.58 | 0.06 | 0.00 | 0.04 | 0.00 | 0.00 | 0.00 | 0.00 | 0.19 | 0.00 | 0.08 | 2.26 | |||||||||||||
| 1963 | 0.06 | 0.51 | 0.44 | 0.41 | 0.00 | 0.07 | 0.00 | 0.81 | 3.94 | 1.92 | 0.29 | 0.00 | 8.45 | |||||||||||||
| 1964 | 0.45 | 0.11 | 0.31 | 0.07 | 0.13 | 0.00 | 0.03 | 0.00 | 0.00 | 0.12 | 1.25 | 0.00 | 2.47 | |||||||||||||
| 1965 | 0.05 | 0.15 | 0.30 | 2.14 | 0.17 | 0.08 | 0.03 | b | 0.52 | 0.08 | 0.00 | 1.93 | 2.00 | 7.45 | ||||||||||||
| 1966 | 0.27 | 0.52 | 0.44 | 0.00 | 0.00 | 0.00 | 0.03 | 0.16 | 0.15 | 0.16 | 0.52 | 0.66 | 2.91 | |||||||||||||
| 1967 | 0.26 | 0.00 | 0.04 | 1.00 | 0.00 | 0.00 | 0.29 | 0.32 | 0.36 | 0.00 | 1.51 | 0.77 | 4.55 | |||||||||||||
| 1968 | 0.06 | 0.09 | 0.48 | 0.26 | 0.00 | 0.12 | 0.74 | 0.00 | 0.04 | 0.05 | 0.27 | 0.25 | 2.36 | |||||||||||||
| 1969 | 1.87 | 3.93 | 0.18 | 0.23 | 0.48 | 0.61 | 0.59 | 0.00 | 0.08 | 0.00 | 0.66 | 0.01 | 8.64 | |||||||||||||
| 1970 | 0.15 | 0.49 | 1.05 | 0.10 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 1.91 | 1.64 | 5.35 | |||||||||||||
| 1971 | 0.04 | 0.34 | 0.12 | 0.18 | 0.15 | 0.00 | 0.28 | 0.00 | 0.00 | 0.29 | 0.02 | 1.10 | 2.52 | |||||||||||||
| 1972 | 0.00 | 0.00 | 0.00 | 0.05 | 0.00 | 0.54 | 0.00 | 0.14 | 0.14 | 1.03 | 0.75 | 0.16 | 2.81 | |||||||||||||
| 1973 | 0.60 | 2.03 | 1.67 | 0.04 | 0.00 | 0.00 | 0.00 | 0.05 | 0.00 | 0.00 | 0.33 | 0.01 | 4.73 | |||||||||||||
| 1974 | 2.00 | 0.00 | 0.29 | 0.07 | 0.58 | 0.00 | 0.46 | 0.78 | 0.00 | 0.16 | 0.00 | 0.93 | 5.27 | |||||||||||||
| 1975 | 0.17 | 0.21 | 1.04 | 0.75 | 0.00 | 0.00 | 0.22 | 0.00 | 0.24 | 0.08 | 0.00 | 0.21 | 2.92 | |||||||||||||
| 1976 | 0.00 | 1.84 | 0.44 | 0.05 | 0.09 | 0.00 | 0.00 | 0.00 | 3.62 | 1.13 | 0.46 | 0.00 | 7.63 | |||||||||||||
| 1977 | 1.15 | 0.04 | 0.52 | 0.00 | 1.35 | 0.04 | 0.00 | 1.43 | 0.00 | 0.00 | 0.08 | 1.77 | 6.38 | |||||||||||||
| 1978 | 1.93 | 3.35 | 3.63 | 0.61 | 0.09 | 0.00 | 0.00 | 0.11 | 0.80 | 0.16 | 0.36 | 0.79 | 11.83 | |||||||||||||
| 1979 | 3.44 | 1.39 | 1.76 | 0.00 | 0.15 | 0.00 | 0.00 | 0.18 | 0.00 | 0.13 | 0.00 | 0.00 | 7.05 | |||||||||||||
| 1980 | 1.89 | 4.45 | 2.06 | 0.39 | 0.42 | 0.04 | 0.00 | 0.00 | 0.05 | 0.00 | 0.00 | 0.02 | 9.32 | |||||||||||||
| 1981 | 0.76 | 0.52 | 1.48 | 0.01 | 0.06 | 0.00 | 0.00 | 0.13 | 0.00 | 0.13 | 0.30 | 0.00 | 3.39 | |||||||||||||
| 1982 | 1.41 | 0.52 | 2.25 | 1.12 | 0.16 | 0.00 | 0.03 | 0.13 | 0.04 | 0.36 | 1.48 | 1.12 | 8.62 | |||||||||||||
| 1983 | 2.39 | 1.61 | 4.80 | 0.93 | 0.00 | 0.00 | 0.00 | 0.83 | 0.49 | 1.20 | 0.57 | 0.60 | 13.42 | |||||||||||||
| 1984 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 1.45 | 0.39 | 0.13 | 0.00 | 0.11 | 4.36 | 6.45 | |||||||||||||
| 1985 | 0.14 | 0.15 | 0.23 | 0.00 | 0.03 | 0.02 | 0.00 | 0.00 | 0.33 | 0.32 | 2.34 | 0.68 | 4.24 | |||||||||||||
| 1986 | 0.30 | 1.30 | 1.19 | 0.85 | 0.00 | 0.00 | 0.15 | 0.18 | 0.08 | 0.35 | 0.77 | 1.08 | 6.25 | |||||||||||||
| 1987 | 1.58 | 0.17 | 0.39 | 0.61 | 0.22 | 0.06 | 0.00 | 0.00 | 0.26 | 1.05 | 0.87 | 1.40 | 6.61 | |||||||||||||
| 1988 | 1.14 | 0.31 | 0.22 | 0.89 | 0.01 | 0.00 | 0.00 | 0.88 | 0.00 | 0.00 | 0.06 | 0.21 | 3.72 | |||||||||||||
| 1989 | 0.93 | 0.26 | 0.00 | 0.00 | 0.54 | 0.00 | 0.00 | 0.03 | 0.51 | 0.02 | 0.01 | 0.04 | 2.34 | |||||||||||||
| 1990 | 1.05 | 0.51 | 0.06 | 0.06 | 0.86 | 0.03 | 0.02 | 1.39 | 0.12 | 0.00 | 0.18 | 0.00 | 4.28 | |||||||||||||
| 1991 | 1.04 | 1.35 | 3.25 | 0.00 | 0.04 | 0.00 | 0.20 | 0.00 | 0.32 | 0.42 | 0.27 | 1.43 | 8.32 | |||||||||||||
| 1992 | 1.46 | 2.51 | 2.59 | 0.17 | 0.02 | 0.00 | 0.31 | 0.00 | 0.00 | 0.36 | 0.00 | 3.68 | 11.10 | |||||||||||||
| 1993 | 4.72 | 2.87 | 0.00 | z | 0.00 | 0.00 | 0.85 | 0.00 | 0.00 | z | 0.00 | 0.01 | 0.19 | 0.41 | 9.05 | |||||||||||
| 1994 | 0.29 | 0.49 | 1.28 | 0.36 | 0.50 | 0.00 | 0.00 | 0.12 | 0.00 | 0.04 | 0.19 | 0.68 | 3.95 | |||||||||||||
| 1995 | 2.91 | 0.62 | 2.63 | 0.12 | 0.07 | 0.03 | 0.03 | 0.03 | 0.17 | 0.00 | 0.00 | 0.62 | 7.23 | |||||||||||||
| 1996 | 0.47 | 1.48 | 0.15 | 0.01 | 0.05 | 0.00 | 0.44 | 0.02 | 0.00 | 0.24 | 0.55 | 0.35 | 3.76 | |||||||||||||
| 1997 | 0.40 | b | 0.00 | 0.01 | 0.00 | 0.34 | 0.06 | 0.00 | 0.00 | 1.36 | 0.01 | 0.43 | 2.65 | 5.26 | ||||||||||||
| 1998 | 0.51 | 5.39 | 1.01 | 0.33 | 0.73 | 0.00 | 0.00 | 0.64 | 1.08 | 0.00 | 0.34 | 0.10 | 10.13 | |||||||||||||
| 1999 | 0.42 | 0.49 | 0.06 | 0.70 | 0.31 | 0.20 | 1.28 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 3.46 | |||||||||||||
| 2000 | 0.03 | 1.23 | 0.17 | 0.84 | 0.00 | 0.00 | 0.00 | 0.03 | c | 0.00 | 0.18 | 0.00 | 0.00 | 2.48 | ||||||||||||
| 2001 | 1.54 | 1.91 | a | 0.70 | 0.30 | 0.01 | 0.00 | 0.27 | 0.00 | 0.00 | 0.15 | 0.63 | 0.52 | 6.03 | ||||||||||||
| 2002 | 0.12 | 0.00 | 0.27 | 0.18 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.05 | 0.13 | 0.53 | 1.28 | |||||||||||||
| 2003 | 0.00 | 3.64 | 1.30 | 1.18 | 0.14 | 0.00 | 0.55 | 0.00 | 0.00 | 0.00 | 1.24 | 0.45 | 8.50 | |||||||||||||
| 2004 | 0.05 | 1.95 | 0.11 | 0.23 | 0.00 | 0.00 | 0.00 | 0.13 | 0.00 | 3.32 | 1.39 | 2.16 | 9.34 | |||||||||||||
| 2005 | 2.20 | 4.17 | 0.43 | 0.05 | 0.00 | 0.00 | z | 0.74 | 0.88 | 0.43 | 1.48 | 0.00 | 0.13 | 10.51 | ||||||||||||
| 2006 | 0.37 | 0.45 | 0.00 | z | 0.68 | 0.00 | 0.02 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.14 | 1.66 | ||||||||||||
| 2007 | 0.07 | 0.18 | 0.00 | z | 0.12 | 0.00 | 0.00 | 0.00 | 0.00 | 0.02 | 0.00 | z | 0.00 | z | 0.92 | 1.31 | ||||||||||
| 2008 | 1.30 | 0.10 | 0.00 | 0.00 | 0.02 | 0.00 | 0.25 | 0.00 | 0.03 | 0.00 | z | 0.00 | z | 0.00 | z | 1.70 | ||||||||||
| 2009 | 0.04 | 1.13 | 0.02 | 0.00 | 0.06 | 0.18 | 0.00 | 0.00 | z | 0.00 | 0.00 | z | 0.00 | z | 0.00 | z | 1.43 | |||||||||
| 2010 | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | |
| 2011 | 0.45 | 1.19 | 1.56 | 0.00 | 0.00 | 0.00 | 0.53 | 0.00 | 0.06 | 0.00 | 0.64 | 0.37 | 4.80 | |||||||||||||
| 2012 | 0.07 | 0.21 | 0.63 | 0.84 | 0.00 | 0.00 | 0.67 | 1.17 | 0.04 | 0.00 | 0.06 | 0.73 | 4.42 | |||||||||||||
| 2013 | 0.46 | 0.28 | 0.14 | b | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.00 | z | 0.88 | |||
| Period of Record Statistics | ||||||||||||||||||||||||||
| MEAN | 0.94 | 1.04 | 0.81 | 0.35 | 0.12 | 0.04 | 0.15 | 0.21 | 0.23 | 0.32 | 0.49 | 0.79 | 5.45 | |||||||||||||
| S.D. | 1.07 | 1.30 | 0.95 | 0.48 | 0.24 | 0.14 | 0.28 | 0.37 | 0.65 | 0.58 | 0.63 | 0.93 | 2.95 | |||||||||||||
| SKEW | 1.37 | 1.77 | 1.90 | 2.25 | 2.88 | 4.46 | 2.64 | 1.85 | 4.62 | 2.82 | 1.59 | 1.78 | 0.80 | |||||||||||||
| MAX | 4.72 | 5.45 | 4.80 | 2.55 | 1.35 | 0.85 | 1.45 | 1.43 | 3.94 | 3.32 | 2.34 | 4.36 | 13.42 | |||||||||||||
| MIN | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 1.27 | |||||||||||||
| NO YRS | 74 | 74 | 71 | 74 | 74 | 73 | 74 | 72 | 74 | 72 | 73 | 74 | 64 | |||||||||||||