Country= U.S.A. Station= ALTON, IL River= MISSISSIPPI RIVER Area= 0.00 Lat= 38.88 Lon= -90.18 Source= USGS PointID= 5587500 Area Units= km2 Discharge Units= m3/sec Starting Year= 1911 Ending Year= 1993 Total Years= 83 Total Usable Years= 79 Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Avg Annual 1911 91.96 109.72 113.26 140.38 419.71 724.82 260.43 99.73 89.21 103.45 109.04 110.4 197.68 1912 111.75 96.83 90.79 120.2 386.81 751.82 368.61 225.56 259.76 197.42 165.43 111.57 240.55 1913 88.13 94.26 118.67 285.79 553.28 708.96 353.96 148.75 218.35 170.31 161.78 117.44 251.64 1914 115.02 95.25 112.13 273.33 509.16 597.3 180.17 104.66 123.54 167.45 160.97 111.08 212.51 1915 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 1916 63.69 81 125.42 272.29 427.68 462.79 289.89 179.65 130.75 144.91 116.07 96.1 199.19 1917 75.65 78.38 81.09 149.13 524.72 737.75 523.31 177.76 131.85 120.89 123.37 119.3 236.93 1918 99.7 84.57 107.41 178.24 314.8 877.36 267.46 198.37 133.51 110.04 115.17 91.75 214.87 1919 75.35 80.95 98.57 192.22 224.3 153.8 77.72 12.34 4.5 42.71 82.69 51.88 91.42 1920 57.84 62.69 62.64 86.82 400.3 322.32 190.08 142.66 58.57 78.86 108.27 91.57 138.55 1921 83.48 82.45 95.94 156.62 521.33 556.09 189.26 136.41 72.82 59.51 94.26 100 179.01 1922 61.58 71.8 92.91 126.91 447.72 385.24 193.54 133.85 48.94 35.26 98.23 85.87 148.49 1923 86.04 63.34 81.06 119.33 354.6 346.71 202.9 122.31 59.42 94.65 99.28 80.62 142.52 1924 70.75 87.22 69.47 90.93 99.89 106.12 80.89 5.46 5.51 44.63 73.69 51.86 65.54 1925 59.37 77.31 78.74 253.96 486.05 343.56 291.23 145.05 104.07 126.78 125.1 112.2 183.62 1926 78.57 95.92 106.51 199.22 122.9 158.97 124.86 38.11 13.09 35.83 71.36 71.29 93.05 1927 62.58 68.15 74.86 104.74 432.74 664.6 320.92 105.59 112.62 114.33 167.13 116.38 195.39 1928 123.13 95.73 107.89 155.89 718.25 448.56 134.7 20.81 26.61 80.02 109.82 104.88 177.19 1929 72.26 69.94 106.88 141.77 237.45 249.12 52.28 35.81 49.08 68.49 88.32 95.66 105.59 1930 53.02 88.58 90.66 168.37 90.76 108.91 58.29 95.18 36.62 95.67 91.9 65.91 86.99 1931 54.02 67.84 74.71 83.2 30.58 9.19 6.07 10.02 5.29 6.13 18.16 35.72 33.41 1932 29.51 29.11 52.74 98.94 276.9 287.53 84.05 23.85 20.06 25.54 74.36 55.84 88.2 1933 69.54 50.71 71.68 105.26 174.73 262.96 37.97 21.49 21.4 8.56 42.69 72.82 78.32 1934 68.14 53.85 33.74 9.34 11.2 17.09 7.38 6.29 4.16 4.67 4.97 31.85 21.06 1935 27.6 34.25 43.62 79.92 160.48 156.03 41.61 76.98 17.43 10.92 68.3 53.29 64.2 1936 50.95 47.12 68.01 166.25 459.1 357.82 34.59 21.18 11.93 20.39 73.93 72 115.27 1937 36.88 53.51 70.42 90.78 222.75 123.14 25.57 17.49 13.02 20.1 51.05 80.83 67.13 1938 65.07 71.14 79.84 176.76 340.98 383.13 188.48 19.34 12.12 76.48 107.89 86.81 134 1939 73.64 59.33 94.56 213.67 167.58 129.4 17.32 20.58 18.66 50.29 57.83 57.96 80.07 1940 61.05 73.05 76.68 121.63 73.8 77.5 26.71 45.78 32.82 55.45 71.2 61.74 64.78 1941 55 60.54 72.1 96.54 117.43 76.31 21.37 37.2 20.76 53.06 77.64 85.88 64.49 1942 50.49 56.21 67.46 205.6 199.95 155.41 49.41 16.17 24.52 36.03 85.91 82.27 85.79 1943 80.01 87.72 107.19 415 345.64 552.56 304.91 22.71 24.79 95.91 142.89 102.55 190.16 1944 67.49 87.82 93.28 113.7 125.94 350.05 59.4 16.78 21.83 30.21 83.13 68.61 93.19 1945 66.95 77.68 78.26 91.34 233.6 331.06 155.47 37.3 71.29 104.61 121.57 90.47 121.63 1946 91.27 111.41 143.96 379.83 304.29 340.34 43.96 27.11 43.72 101.09 117.8 106.31 150.92 1947 57.68 81.47 94.2 141.58 299.7 396.72 56.22 40.96 64.02 81.02 109.95 96.24 126.65 1948 79.56 85.55 89.69 160.19 384.67 471.11 70.87 30.78 37.36 74.37 90.09 72.95 137.27 1949 51.36 59.55 114.8 204.9 361.81 321.62 43.08 27.41 27.07 101.02 110.06 85.82 125.71 1950 64.13 84.86 109.82 247.21 304.18 545.48 287.87 49.57 83.45 126.83 140.95 131.66 181.33 1951 113.42 158.49 188.06 302.09 446.22 350.36 127.01 149.52 73.59 128.7 149.83 118.64 192.16 1952 117.2 147.33 169.33 334.65 520.21 394.2 82.68 41.89 33.4 43.08 93.24 100.38 173.13 1953 122.33 104.7 96.05 109.89 130.89 397.62 72.54 32.62 30.87 54.01 98.77 92.19 111.87 1954 88.71 89.43 88.53 135.55 306.56 199.58 135.16 37.29 40.94 74.49 100.85 80.82 114.83 1955 69.96 67.48 83.11 114.33 156.31 190.14 60.86 34.47 27.3 48.21 96.08 125.64 89.49 1956 118.36 75.11 140.68 356.48 480.93 537.74 95.66 42.7 39.68 79.08 104.91 90.01 180.11 1957 63.61 93.84 146.59 178.64 459.7 190.23 41.15 39.62 42.31 65.92 104.11 106.12 127.65 1958 93.29 103.83 95.62 123.99 260.99 120.32 31.37 37.08 44.69 31.59 91.05 91.32 93.76 1959 84.65 91.04 89.45 78.23 49.75 66.23 68.47 75.68 113.36 82.69 96.83 88.01 82.03 1960 64.24 63.23 82.94 92.96 54.33 65.43 52.81 120.58 80.29 41.24 63.35 58.25 69.97 1961 59.18 69.87 65.41 72.25 50.07 41.92 46 48.17 60.63 56.36 66.05 65.27 58.43 1962 55.17 107.66 73.77 171.5 296.63 153.07 54.24 46.3 42.35 52.74 76.64 96.13 102.18 1963 56.63 90.59 67.6 57.52 252.96 443.52 22.58 27.78 32.67 21.15 72.89 70.87 101.4 1964 57.72 60.34 76.03 190.14 394.04 419.54 147.25 43.76 35.46 57.36 95.31 111.91 140.74 1965 127.27 231.13 333.23 373.31 343.83 250.75 193.81 90.45 92.82 116 138.03 163.54 204.51 1966 125.01 129.2 116.26 137.01 174.34 64 41.38 136.02 78.91 57.7 70.83 76.99 100.64 1967 72.03 71.05 69.19 66 229.37 345.07 184.95 58.92 27.6 83.49 108.14 113.04 119.07 1968 106.42 84.35 85.14 134.12 219.56 301.28 39.04 132.54 51.76 74.85 108.75 135.78 122.8 1969 153.08 146.64 184.95 425.05 243.86 154.21 59.82 53.79 45.39 76.62 81.52 72.8 141.48 1970 81 85.52 80.3 157.59 427.32 382.08 158.24 50.23 87.75 90.33 123.09 129.53 154.42 1971 138.74 177.63 258.44 543.78 613.02 479.03 330.19 99.68 192.34 274.16 194.72 157.11 288.24 1972 148.8 178.54 322.79 516.5 411.69 438.28 89.45 100.28 155.19 185.48 162.88 165.65 239.63 1973 131.08 150.64 133.58 163.85 199.45 149.9 123.19 64.24 59.25 71.13 95.45 92.99 119.56 1974 104.27 125.91 207.85 524.05 482.21 454.77 186.96 65.35 48.95 117.08 151.09 139.68 217.35 1975 133.99 128.5 203.29 345.19 428.13 312.94 226.46 90.92 57.27 115.12 142.43 151.59 194.65 1976 153.17 153.87 264.68 468.93 640.33 333.94 87.23 103.45 68.89 91.35 106.27 157.15 219.11 1977 125.54 77.64 51.75 55.66 95.55 62.84 48.92 74.19 24.61 19.67 48.85 58.22 61.95 1978 58.55 61.07 94.01 238.02 327.08 238.16 113.39 58.38 54.9 34.29 91.38 129.51 124.9 1979 144.54 148.46 199.84 222.83 156.86 146.37 72.97 55.84 16.25 37.39 56.68 66.86 110.41 1980 67.8 75.41 62.64 154.75 350.38 380.24 80.99 52.51 31.75 42.59 68.57 66.76 119.53 1981 62.74 66.86 55.53 105.79 242.91 336.08 54.66 30.82 20.79 36.8 53.93 58.91 93.82 1982 51.36 69.37 221.31 354.61 518.66 295.3 325.22 91.95 107.08 167.6 170.63 168.29 211.78 1983 189.72 149.29 168.09 256.5 522.22 542.27 363.37 131.43 77.25 177.64 222.34 232.98 252.76 1984 227.27 148.95 163.64 392.93 580.13 635.43 363.38 198.79 170.82 153.98 173.53 201.85 284.23 1985 212.92 173.15 161.72 307.49 413.97 182.81 52.59 45.06 71.73 78.5 98.21 98.28 158.04 1986 128.67 138.16 366.05 521.98 584.43 536.04 211.95 70.29 136.86 145.38 158.58 181.67 265.01 1987 159.83 111.22 91.95 99.51 112.06 94.25 71.66 47.38 37.49 46.84 64.61 55.02 82.65 1988 56.15 51.43 50.3 65.55 41.7 57.79 79.5 82.75 57.26 36 63.25 47.78 57.46 1989 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 1990 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 1991 52.45 66.5 68.47 49.23 122.69 163.81 58.11 44.3 37.68 49.92 90.22 62.38 72.15 1992 51.69 59.65 47.11 48.13 71.51 103.74 69.48 64.27 48.11 49.06 55.15 50.54 59.87 1993 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 Avg 88.09 92.4 113.63 195.75 307.35 317.22 132.25 70.49 60.9 78.98 101.54 96.81 137.95 Std Dev 39.68 37.26 65.57 126.41 168.65 198.69 110.29 51.04 49.76 50.39 39.05 37.79 62.59