Wellsville Water Treatment Plant total monthly precipitation and yearly totals.
Yellow highlight is low and Pink highlight is high monthly total precipitation for the year.
1940 – 1959
| Year | Jan | Feb | March | April | May | June | July | Aug | Sep | Oct | Nov | Dec | Total |
| 1940 | 0.87 | 2.35 | 3.35 | 3.69 | 2.26 | 4.20 | 1.94 | 4.29 | 3.31 | 1.50 | 2.43 | 2.80 | 32.99 |
| 1941 | 1.36 | 0.41 | 2.01 | 2.00 | 2.99 | 3.14 | 5.85 | 2.07 | 1.19 | 3.48 | 0.59 | 1.77 | 26.86 |
| 1942 | 0.94 | 1.83 | 4.49 | 1.85 | 4.48 | 3.09 | 8.04 | 2.70 | 5.38 | 2.80 | 3.17 | 4.44 | 43.21 |
| 1943 | 1.93 | 1.31 | 1.97 | 4.41 | 6.24 | 2.40 | 2.51 | 2.63 | 1.10 | 4.04 | 2.83 | 0.63 | 32.00 |
| 1944 | 1.18 | 2.20 | 2.64 | 2.76 | 4.32 | 4.72 | 1.93 | 1.13 | 4.86 | 2.29 | 2.11 | 3.99 | 34.13 |
| 1945 | 1.82 | 2.81 | 4.44 | 3.74 | 4.39 | 5.29 | 4.77 | 3.30 | 6.19 | 3.86 | 4.11 | 1.46 | 46.18 |
| 1946 | 0.71 | 1.69 | 1.81 | 1.63 | 6.48 | 5.59 | 5.68 | 3.24 | 3.38 | 3.28 | 1.47 | 1.98 | 36.94 |
| 1947 | 3.36 | 0.67 | 1.91 | 5.56 | 6.74 | 3.78 | 4.14 | 4.02 | 2.69 | 0.69 | 2.76 | 1.54 | 37.86 |
| 1948 | 2.63 | 1.78 | 5.64 | 4.40 | 4.30 | 4.58 | 3.46 | 3.74 | 1.26 | 2.35 | 2.95 | 2.91 | 40.00 |
| 1949 | 2.05 | 1.51 | 2.06 | 2.79 | 3.22 | 1.14 | 2.42 | 3.35 | 2.00 | 0.89 | 1.85 | 2.59 | 25.87 |
| 1950 | 4.20 | 3.09 | 3.71 | 2.74 | 3.52 | 3.21 | 3.66 | 3.72 | 1.22 | 3.72 | 7.21 | 3.59 | 43.59 |
| 1951 | 3.59 | 2.62 | 3.25 | 3.21 | 1.06 | 5.37 | 4.51 | 1.45 | 3.61 | 1.08 | 4.06 | 3.25 | 37.06 |
| 1952 | 3.75 | 2.66 | 2.18 | 3.35 | 4.11 | 1.19 | 1.58 | 2.63 | 3.65 | 2.28 | 2.49 | 1.91 | 31.78 |
| 1953 | 2.70 | 1.77 | 3.56 | 2.09 | 4.99 | 1.73 | 3.35 | 1.92 | 3.76 | 1.42 | 1.96 | 2.16 | 31.41 |
| 1954 | 1.90 | 1.69 | 3.13 | 4.16 | 3.67 | 4.23 | 1.85 | 3.21 | 2.47 | 2.19 | 1.47 | 3.03 | 33.00 |
| 1955 | 0.90 | 2.50 | 3.84 | 1.35 | 1.84 | 1.35 | 3.40 | 4.75 | 1.38 | 6.65 | 3.37 | 0.92 | 32.25 |
| 1956 | 1.14 | 3.38 | 5.36 | 2.72 | 4.23 | 1.94 | 6.77 | 4.82 | 3.23 | 1.37 | 2.66 | 2.99 | 40.61 |
| 1957 | 2.12 | 1.46 | 1.87 | 5.83 | 3.99 | 2.05 | 3.32 | 0.95 | 1.53 | 0.85 | 1.72 | 2.86 | 28.55 |
| 1958 | 2.27 | 1.48 | 1.80 | 3.62 | 3.16 | 5.52 | 5.38 | 3.87 | 4.84 | 1.42 | 3.08 | 1.08 | 37.52 |
| 1959 | 3.87 | 2.33 | 2.73 | 2.99 | 2.06 | 2.76 | 2.70 | 0.94 | 2.15 | 5.55 | 3.97 | 2.69 | 34.74 |
1960-1979
| Year | Jan | Feb | March | April | May | June | July | Aug | Sep | Oct | Nov | Dec | Total |
| 1960 | 2.48 | 2.17 | 1.81 | 1.91 | 4.83 | 5.41 | 1.28 | 3.55 | 1.87 | 1.02 | 1.28 | 1.54 | 29.15 |
| 1961 | 0.41 | 6.14 | 2.43 | 5.13 | 3.04 | 4.84 | 4.31 | 3.43 | 0.69 | 2.77 | 2.31 | 1.03 | 36.53 |
| 1962 | 1.03 | 1.53 | 1.75 | 2.71 | 2.11 | 2.43 | 1.88 | 1.08 | 3.61 | 3.57 | 2.23 | 2.16 | 26.09 |
| 1963 | 1.26 | 0.85 | 2.04 | 2.75 | 2.63 | 1.19 | 4.81 | 2.03 | 2.02 | 0.48 | 4.20 | 1.14 | 25.40 |
| 1964 | 1.91 | 1.21 | 4.98 | 3.16 | 1.51 | 2.21 | 1.05 | 5.40 | 0.80 | 1.06 | 1.63 | 3.47 | 28.39 |
| 1965 | 3.08 | 1.88 | 1.38 | 2.84 | 3.65 | 2.61 | 3.20 | 2.09 | 3.28 | 2.99 | 3.60 | 1.72 | 32.32 |
| 1966 | 2.17 | 2.72 | 2.17 | 2.47 | 1.38 | 4.91 | 1.25 | 1.70 | 4.52 | 1.22 | 4.70 | 1.32 | 30.53 |
| 1967 | 1.30 | 1.72 | 2.65 | 2.85 | 4.10 | 4.63 | 4.85 | 5.73 | 4.74 | 3.41 | 2.94 | 1.51 | 40.43 |
| 1968 | 1.41 | 0.46 | 2.85 | 1.52 | 5.05 | 3.75 | 1.05 | 2.08 | 3.07 | 2.04 | 3.95 | 2.77 | 30.00 |
| 1969 | 1.16 | 0.80 | 0.75 | 4.84 | 2.07 | 6.81 | 3.33 | 2.35 | 1.21 | 2.93 | 3.48 | 3.59 | 33.32 |
| 1970 | 1.00 | 2.51 | 1.00 | 2.59 | 2.94 | 2.44 | 5.22 | 1.17 | 4.21 | 3.53 | 3.21 | 2.57 | 32.39 |
| 1971 | 1.31 | 2.95 | 1.40 | 1.78 | 1.63 | 4.03 | 1.84 | 1.36 | 2.67 | 1.55 | 1.80 | 3.67 | 25.99 |
| 1972 | 2.11 | 2.78 | 2.44 | 2.58 | 4.15 | 16.20 | 3.03 | 4.10 | 2.90 | 2.34 | 4.26 | 3.22 | 50.11 |
| 1973 | 1.25 | 1.74 | 2.75 | 2.32 | 2.91 | 2.53 | 3.30 | 2.91 | 2.68 | 3.10 | 1.65 | 2.54 | 29.68 |
| 1974 | 1.71 | 1.86 | 3.89 | 4.13 | 2.97 | 2.24 | 2.06 | 3.17 | 3.36 | 1.06 | 3.68 | 2.38 | 32.51 |
| 1975 | 1.53 | 2.08 | 2.06 | 0.78 | 3.62 | 4.84 | 3.62 | 3.90 | 5.92 | 2.72 | 1.59 | 3.19 | 35.85 |
| 1976 | 6.32 | 3.52 | 4.08 | 2.49 | 2.80 | 5.29 | 3.77 | 1.03 | 2.22 | 5.48 | 0.66 | 1.47 | 39.13 |
| 1977 | 0.81 | 0.45 | 2.24 | 1.90 | 2.21 | 3.44 | 8.80 | 4.83 | 8.76 | 1.79 | 2.79 | 4.02 | 42.04 |
| 1978 | 6.38 | 0.64 | 1.01 | 1.72 | 4.34 | 3.78 | 2.82 | 2.86 | 2.36 | 3.47 | 0.64 | 4.20 | 34.22 |
| 1979 | 4.66 | 1.43 | 1.92 | 2.16 | 2.55 | 2.06 | 5.08 | 3.21 | 3.06 | 2.87 | 2.85 | 1.96 | 33.81 |
1980-1999
| Year | Jan | Feb | March | April | May | June | July | Aug | Sep | Oct | Nov | Dec | Total |
| 1980 | 0.40 | 0.84 | 3.15 | 2.59 | 1.25 | 4.03 | 1.28 | 2.98 | 2.10 | 3.90 | 1.79 | 1.68 | 25.99 |
| 1981 | 0.73 | 3.09 | 1.13 | 1.98 | 2.15 | 3.83 | 3.03 | 0.74 | 3.89 | 5.69 | 1.93 | 1.61 | 29.80 |
| 1982 | 3.33 | 1.11 | 1.89 | 1.10 | 3.41 | 6.54 | 2.13 | 1.49 | 1.95 | 1.61 | 2.44 | 1.54 | 28.54 |
| 1983 | 0.90 | 0.57 | 2.50 | 3.90 | 3.55 | 3.27 | 2.60 | 3.05 | 2.37 | 2.10 | 3.53 | 3.58 | 31.92 |
| 1984 | 1.30 | 2.86 | 2.84 | 3.52 | 7.13 | 3.89 | 3.43 | 6.41 | 2.48 | 2.42 | 2.42 | 3.17 | 41.87 |
| 1985 | 1.27 | 1.24 | 4.23 | 0.68 | 3.99 | 3.16 | 2.73 | 2.68 | 2.30 | 2.37 | 6.02 | 2.05 | 32.72 |
| 1986 | 1.91 | 2.19 | 1.47 | 2.67 | 2.74 | 5.92 | 6.02 | 2.69 | 4.53 | 3.12 | 2.17 | 2.01 | 37.44 |
| 1987 | 1.80 | 0.77 | 2.08 | 3.12 | 1.21 | 5.47 | 4.48 | 3.20 | 7.93 | 1.97 | 2.26 | 1.83 | 36.12 |
| 1988 | 0.63 | 2.37 | 1.64 | 3.16 | 3.21 | 1.48 | 5.75 | 2.63 | 1.69 | 3.38 | 2.19 | 1.58 | 29.71 |
| 1989 | 1.38 | 1.59 | 3.43 | 0.93 | 6.23 | 9.05 | 2.98 | 1.62 | 3.70 | 2.95 | 2.94 | 0.84 | 37.64 |
| 1990 | 1.97 | 2.36 | 1.22 | 2.80 | 5.46 | 1.47 | 3.33 | 3.24 | 5.44 | 5.82 | 1.62 | 3.96 | 38.69 |
| 1991 | 1.64 | 1.17 | 3.13 | 3.50 | 1.61 | 0.55 | 4.33 | 2.98 | 2.96 | 2.13 | 1.40 | 2.33 | 27.73 |
| 1992 | 1.43 | 0.71 | 2.68 | 3.44 | 2.09 | 2.36 | 8.24 | 3.06 | 3.88 | 3.37 | 3.11 | 2.42 | 36.79 |
| 1993 | 1.50 | 0.99 | 3.21 | 4.65 | 1.43 | 3.49 | 2.44 | 3.01 | 6.24 | 3.04 | 3.56 | 1.46 | 35.02 |
| 1994 | 2.29 | 1.99 | 2.99 | 5.82 | 3.23 | 5.14 | 2.01 | 10.13 | 1.86 | 3.40 | 2.90 | 1.93 | 43.69 |
| 1995 | 2.54 | 0.98 | 0.93 | 2.51 | 2.17 | 1.59 | 2.35 | 1.23 | 1.57 | 6.81 | 3.47 | 1.60 | 27.75 |
| 1996 | 4.43 | 1.48 | 2.42 | 5.35 | 4.70 | 3.01 | 3.70 | 2.56 | 6.74 | 4.84 | 3.99 | 1.72 | 44.94 |
| 1997 | 2.45 | 2.43 | 3.30 | 2.99 | 3.62 | 5.50 | 3.60 | 1.85 | 4.52 | 0.94 | 3.80 | 1.84 | 37.86 |
| 1998 | 3.77 | 1.94 | 1.59 | 4.71 | 3.33 | 8.45 | 4.35 | 2.78 | 0.99 | 2.65 | 0.64 | 1.92 | 37.12 |
| 1999 | 4.18 | 0.92 | 2.72 | 2.88 | 2.22 | 2.84 | 5.52 | 3.41 | 4.23 | 1.91 | 3.30 | 1.66 | 35.79 |
2000 – 2019
| Year | Jan | Feb | March | April | May | June | July | Aug | Sep | Oct | Nov | Dec | Total |
| 2000 | 2.69 | 2.08 | 1.82 | 3.93 | 5.61 | 5.99 | 1.41 | 4.34 | 3.30 | 3.23 | 1.57 | 1.26 | 37.23 |
| 2001 | 0.64 | 0.57 | 3.72 | 2.21 | 2.58 | 2.31 | 1.02 | 4.14 | 3.03 | 3.00 | 2.82 | 2.02 | 28.06 |
| 2002 | 1.41 | 1.30 | 2.28 | 3.71 | 0.18 | 7.55 | 2.60 | 2.76 | 2.56 | 3.01 | 2.41 | 4.04 | 33.81 |
| 2003 | 3.00 | 1.71 | 1.76 | 2.77 | 4.67 | 3.40 | 10.91 | 5.24 | 4.90 | 2.93 | 4.45 | 4.48 | 50.22 |
| 2004 | 3.08 | 0.68 | 2.62 | 4.50 | 6.33 | 2.11 | 5.09 | 5.26 | 5.51 | 2.25 | 3.01 | 3.27 | 43.71 |
| 2005 | 4.64 | 1.36 | 1.23 | 4.20 | 0.89 | 2.08 | 3.42 | 8.51 | 3.18 | 4.73 | 4.50 | 1.43 | 41.17 |
| 2006 | 2.82 | 1.45 | 1.33 | 3.11 | 2.96 | 4.92 | 5.43 | 4.95 | 4.36 | 5.03 | 2.52 | 2.20 | 41.05 |
| 2007 | 4.66 | 1.84 | 2.73 | 1.95 | 1.13 | 2.58 | 4.18 | 3.38 | 4.61 | 2.37 | 3.35 | 4.30 | 37.08 |
| 2008 | 1.36 | 3.94 | 4.94 | 1.81 | 2.33 | 3.91 | 6.61 | 5.54 | 2.59 | 2.62 | 2.14 | 3.48 | 41.27 |
| 2009 | 1.95 | 1.32 | 2.40 | 1.63 | 3.41 | 6.21 | 3.02 | 6.27 | 1.98 | 3.16 | 0.54 | 2.14 | 34.03 |
| 2010 | 2.91 | 1.92 | 2.45 | 2.18 | 4.12 | 4.89 | 6.23 | 4.07 | 4.58 | 4.14 | 4.34 | 2.10 | 43.93 |
| 2011 | 1.70 | 4.07 | 3.88 | 7.65 | 9.09 | 2.96 | 0.58 | 4.17 | 4.36 | 4.02 | 2.82 | 2.64 | 47.94 |
| 2012 | 2.95 | 1.08 | 1.71 | 2.40 | 2.75 | 3.21 | 6.00 | 1.92 | 3.89 | 5.96 | 0.67 | 6.77 | 39.31 |
| 2013 | 2.43 | 1.30 | 0.79 | 3.38 | 4.67 | 4.02 | 3.38 | 2.57 | 2.55 | 5.04 | 2.93 | 2.33 | 35.39 |
| 2014 | 1.64 | 2.34 | 2.33 | 2.34 | 5.00 | 5.00 | 3.62 | 3.39 | 2.13 | 2.41 | 1.84 | 2.34 | 34.38 |
| 2015 | 1.00 | 1.76 | 1.23 | 3.41 | 2.20 | 5.61 | 2.11 | 2.87 | 6.50 | 3.18 | 2.12 | 3.56 | 35.55 |
| 2016 | 1.55 | 3.32 | 2.35 | 2.54 | 3.31 | 2.38 | 2.33 | 4.96 | 2.75 | 8.25 | 1.58 | 2.51 | 37.83 |
| 2017 | 3.75 | 2.83 | 3.29 | 2.91 | 4.56 | 3.72 | 4.77 | 1.56 | 2.39 | 5.49 | 2.96 | 2.03 | 40.26 |
| 2018 | 4.18 | 2.42 | 2.86 | 2.81 | 4.46 | 4.30 | 6.84 | 5.02 | 5.63 | 5.95 | 4.41 | 2.36 | 51.24 |
| 2019 | 2.74 | 2.45 | 1.20 | 3.88 | 4.00 | 4.65 | 4.71 | 4.29 | 2.88 | 5.19 | 1.40 | 2.93 | 40.32 |
2020-2039
| Year | Jan | Feb | March | April | May | June | July | Aug | Sep | Oct | Nov | Dec | Total |
| 2020 | 2.09 | 3.70 | 2.71 | 2.45 | 3.21 | 4.34 | 3.63 | 2.96 | 2.28 | 3.59 | 1.98 | 2.83 | 35.77 |
| 2021 | 1.39 | 1.62 | 1.38 | 3.70 | 4.08 | 6.24 | 7.11 | 5.24 | 3.56 | 5.35 | 1.94 | 2.63 | 44.24 |
| 2022 | 1.95 | 4.26 | 2.33 | 2.54 | 2.43 | 2.56 | 4.56 | 3.24 | 5.91 | .75 | 3.74 | 2.44 | 36.71 |
| 2023 | 3.07 | 1.74 | 2.21 | 2.31 | 2.51 | 3.18 | 4.64 | 4.28 | 2.67 | 2.55 | 1.42 | 3.48 | 34.06 |
| 2024 | 4.28 | 1.09 | 2.56 | 4.92 | 3.65 | 6.08 | 5.42 | 5.43 | 4.40 | 1.79 | 2.82 | ||
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