Historical Monthly Mean Water Levels from the Coordinated network for Lake Superior

Monthly mean water levels in metres referred to IGLD 1985

Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Average Min Max Range
1918 183.25 183.20 183.17 183.14 183.22 183.34 183.40 183.43 183.45 183.44 183.46 183.44 183.33 183.14 183.46 0.32
1919 183.38 183.32 183.28 183.31 183.38 183.45 183.48 183.47 183.46 183.42 183.43 183.39 183.40 183.28 183.48 0.20
1920 183.29 183.27 183.28 183.36 183.43 183.52 183.58 183.60 183.54 183.50 183.43 183.36 183.43 183.27 183.60 0.33
1921 183.31 183.22 183.18 183.23 183.35 183.44 183.48 183.50 183.50 183.44 183.35 183.27 183.36 183.18 183.50 0.32
1922 183.17 183.11 183.09 183.15 183.29 183.36 183.45 183.50 183.52 183.45 183.39 183.31 183.32 183.09 183.52 0.43
1923 183.23 183.15 183.12 183.11 183.18 183.21 183.27 183.30 183.32 183.30 183.28 183.22 183.22 183.11 183.32 0.21
1924 183.15 183.07 183.01 183.02 183.05 183.09 183.12 183.20 183.26 183.28 183.20 183.11 183.13 183.01 183.28 0.27
1925 183.02 182.96 182.93 182.94 182.98 183.06 183.12 183.16 183.15 183.10 183.01 182.92 183.03 182.92 183.16 0.24
1926 182.83 182.76 182.74 182.72 182.76 182.85 182.96 183.02 183.12 183.19 183.18 183.19 182.94 182.72 183.19 0.47
1927 183.12 183.08 183.07 183.12 183.27 183.39 183.50 183.52 183.50 183.49 183.44 183.38 183.32 183.07 183.52 0.45
1928 183.31 183.24 183.20 183.25 183.36 183.44 183.56 183.62 183.69 183.74 183.68 183.57 183.47 183.20 183.74 0.54
1929 183.46 183.42 183.44 183.47 183.47 183.51 183.57 183.56 183.56 183.55 183.52 183.44 183.50 183.42 183.57 0.15
1930 183.37 183.34 183.30 183.28 183.39 183.48 183.58 183.58 183.53 183.53 183.47 183.42 183.44 183.28 183.58 0.30
1931 183.33 183.25 183.18 183.16 183.22 183.30 183.39 183.41 183.40 183.42 183.43 183.42 183.33 183.16 183.43 0.27
1932 183.37 183.34 183.30 183.28 183.38 183.45 183.52 183.58 183.58 183.48 183.45 183.38 183.43 183.28 183.58 0.30
1933 183.32 183.28 183.24 183.28 183.43 183.52 183.56 183.57 183.57 183.57 183.53 183.47 183.44 183.24 183.57 0.33
1934 183.42 183.37 183.34 183.36 183.47 183.55 183.58 183.55 183.58 183.61 183.59 183.55 183.50 183.34 183.61 0.27
1935 183.47 183.42 183.40 183.40 183.47 183.53 183.62 183.65 183.63 183.57 183.52 183.44 183.51 183.40 183.65 0.25
1936 183.39 183.34 183.33 183.35 183.51 183.59 183.59 183.57 183.57 183.51 183.43 183.33 183.46 183.33 183.59 0.26
1937 183.31 183.29 183.27 183.27 183.42 183.50 183.54 183.60 183.61 183.58 183.57 183.49 183.45 183.27 183.61 0.34
1938 183.42 183.38 183.35 183.43 183.62 183.72 183.73 183.72 183.69 183.61 183.57 183.49 183.56 183.35 183.73 0.38
1939 183.46 183.43 183.40 183.42 183.52 183.66 183.75 183.75 183.71 183.62 183.51 183.43 183.56 183.40 183.75 0.35
1940 183.33 183.25 183.18 183.16 183.28 183.45 183.53 183.55 183.53 183.48 183.46 183.39 183.38 183.16 183.55 0.39
1941 183.32 183.25 183.18 183.21 183.34 183.44 183.49 183.52 183.61 183.71 183.66 183.57 183.44 183.18 183.71 0.53
1942 183.48 183.41 183.38 183.38 183.51 183.59 183.61 183.62 183.65 183.64 183.65 183.60 183.54 183.38 183.65 0.27
1943 183.53 183.49 183.45 183.44 183.56 183.73 183.80 183.80 183.75 183.67 183.59 183.48 183.61 183.44 183.80 0.36
1944 183.36 183.28 183.24 183.23 183.38 183.55 183.66 183.76 183.78 183.70 183.62 183.52 183.51 183.23 183.78 0.55
1945 183.42 183.38 183.38 183.51 183.53 183.56 183.63 183.65 183.70 183.64 183.58 183.52 183.54 183.38 183.70 0.32
1946 183.45 183.40 183.36 183.42 183.45 183.52 183.60 183.61 183.62 183.62 183.63 183.57 183.52 183.36 183.63 0.27
1947 183.47 183.38 183.32 183.36 183.49 183.67 183.75 183.74 183.73 183.66 183.57 183.46 183.55 183.32 183.75 0.43
1948 183.37 183.27 183.21 183.27 183.40 183.42 183.46 183.51 183.53 183.45 183.43 183.40 183.39 183.21 183.53 0.32
1949 183.33 183.28 183.22 183.24 183.36 183.44 183.57 183.64 183.60 183.60 183.56 183.48 183.44 183.22 183.64 0.42
1950 183.42 183.37 183.33 183.37 183.57 183.74 183.82 183.86 183.83 183.82 183.77 183.69 183.63 183.33 183.86 0.53
1951 183.57 183.51 183.52 183.59 183.71 183.75 183.80 183.80 183.83 183.84 183.79 183.70 183.70 183.51 183.84 0.33
1952 183.63 183.56 183.50 183.52 183.58 183.62 183.77 183.86 183.82 183.67 183.52 183.46 183.63 183.46 183.86 0.40
1953 183.37 183.32 183.28 183.33 183.40 183.57 183.69 183.72 183.67 183.57 183.45 183.40 183.48 183.28 183.72 0.44
1954 183.31 183.25 183.20 183.22 183.44 183.57 183.62 183.59 183.52 183.47 183.41 183.33 183.41 183.20 183.62 0.42
1955 183.24 183.17 183.16 183.21 183.30 183.37 183.39 183.47 183.45 183.49 183.47 183.40 183.34 183.16 183.49 0.33
1956 183.31 183.25 183.16 183.16 183.22 183.32 183.43 183.48 183.48 183.42 183.37 183.30 183.32 183.16 183.48 0.32
1957 183.21 183.13 183.12 183.14 183.26 183.35 183.46 183.48 183.48 183.43 183.40 183.34 183.32 183.12 183.48 0.36
1958 183.26 183.21 183.16 183.14 183.18 183.24 183.36 183.40 183.47 183.44 183.43 183.37 183.30 183.14 183.47 0.33
1959 183.28 183.21 183.19 183.18 183.29 183.40 183.46 183.52 183.63 183.64 183.56 183.44 183.40 183.18 183.64 0.46
1960 183.37 183.30 183.22 183.24 183.47 183.56 183.56 183.55 183.53 183.45 183.40 183.34 183.42 183.22 183.56 0.34
1961 183.24 183.18 183.17 183.19 183.29 183.36 183.38 183.38 183.42 183.41 183.39 183.33 183.31 183.17 183.42 0.25
1962 183.24 183.18 183.15 183.15 183.25 183.35 183.38 183.41 183.47 183.45 183.35 183.28 183.30 183.15 183.47 0.32
1963 183.19 183.14 183.11 183.18 183.24 183.35 183.41 183.44 183.44 183.41 183.36 183.29 183.30 183.11 183.44 0.33
1964 183.21 183.15 183.09 183.09 183.30 183.41 183.48 183.51 183.54 183.51 183.45 183.36 183.34 183.09 183.54 0.45
1965 183.28 183.21 183.16 183.18 183.31 183.38 183.41 183.44 183.43 183.45 183.41 183.39 183.34 183.16 183.45 0.29
1966 183.33 183.27 183.26 183.28 183.36 183.47 183.49 183.54 183.52 183.47 183.42 183.37 183.40 183.26 183.54 0.28
1967 183.31 183.26 183.21 183.29 183.39 183.45 183.50 183.53 183.49 183.44 183.41 183.34 183.38 183.21 183.53 0.32
1968 183.26 183.19 183.14 183.23 183.33 183.49 183.63 183.72 183.79 183.78 183.71 183.61 183.49 183.14 183.79 0.65
1969 183.56 183.53 183.46 183.46 183.55 183.57 183.58 183.59 183.54 183.50 183.44 183.35 183.51 183.35 183.59 0.24
1970 183.30 183.24 183.19 183.18 183.36 183.50 183.59 183.61 183.60 183.59 183.65 183.60 183.45 183.18 183.65 0.47
1971 183.51 183.45 183.44 183.47 183.56 183.66 183.70 183.70 183.67 183.65 183.62 183.56 183.58 183.44 183.70 0.26
1972 183.48 183.42 183.42 183.43 183.55 183.58 183.60 183.68 183.71 183.68 183.60 183.49 183.55 183.42 183.71 0.29
1973 183.43 183.36 183.38 183.43 183.58 183.67 183.73 183.80 183.80 183.74 183.65 183.58 183.60 183.36 183.80 0.44
1974 183.50 183.44 183.39 183.40 183.52 183.63 183.72 183.77 183.79 183.77 183.76 183.69 183.62 183.39 183.79 0.40
1975 183.62 183.57 183.51 183.46 183.55 183.62 183.69 183.68 183.66 183.60 183.59 183.58 183.59 183.46 183.69 0.23
1976 183.49 183.42 183.40 183.49 183.57 183.59 183.63 183.62 183.55 183.46 183.35 183.24 183.48 183.24 183.63 0.39
1977 183.16 183.10 183.13 183.20 183.27 183.31 183.40 183.44 183.58 183.65 183.62 183.54 183.37 183.10 183.65 0.55
1978 183.48 183.36 183.31 183.30 183.35 183.44 183.52 183.57 183.61 183.55 183.43 183.34 183.44 183.30 183.61 0.31
1979 183.25 183.21 183.24 183.31 183.50 183.65 183.68 183.68 183.67 183.61 183.60 183.53 183.49 183.21 183.68 0.47
1980 183.47 183.40 183.33 183.35 183.39 183.43 183.46 183.49 183.55 183.53 183.46 183.37 183.44 183.33 183.55 0.22
1981 183.27 183.22 183.22 183.32 183.40 183.47 183.51 183.49 183.41 183.38 183.35 183.28 183.36 183.22 183.51 0.29
1982 183.23 183.16 183.13 183.19 183.35 183.41 183.50 183.57 183.58 183.65 183.67 183.61 183.42 183.13 183.67 0.54
1983 183.56 183.49 183.47 183.48 183.51 183.59 183.64 183.63 183.61 183.64 183.61 183.58 183.57 183.47 183.64 0.17
1984 183.49 183.44 183.40 183.39 183.49 183.59 183.65 183.66 183.63 183.61 183.58 183.55 183.54 183.39 183.66 0.27
1985 183.48 183.42 183.41 183.45 183.58 183.66 183.74 183.81 183.86 183.91 183.89 183.81 183.67 183.41 183.91 0.50
1986 183.70 183.63 183.61 183.68 183.74 183.76 183.81 183.84 183.81 183.79 183.75 183.67 183.73 183.61 183.84 0.23
1987 183.58 183.50 183.44 183.41 183.42 183.46 183.50 183.55 183.53 183.46 183.40 183.37 183.47 183.37 183.58 0.21
1988 183.29 183.22 183.17 183.20 183.24 183.26 183.27 183.39 183.44 183.41 183.46 183.46 183.32 183.17 183.46 0.29
1989 183.41 183.33 183.28 183.31 183.39 183.50 183.53 183.52 183.50 183.41 183.38 183.27 183.40 183.27 183.53 0.26
1990 183.19 183.13 183.09 183.08 183.18 183.25 183.35 183.36 183.38 183.39 183.38 183.31 183.26 183.08 183.39 0.31
1991 183.23 183.16 183.14 183.22 183.32 183.37 183.46 183.46 183.44 183.43 183.46 183.45 183.34 183.14 183.46 0.32
1992 183.37 183.30 183.25 183.22 183.32 183.36 183.45 183.47 183.52 183.54 183.50 183.47 183.40 183.22 183.54 0.32
1993 183.41 183.32 183.24 183.24 183.38 183.48 183.56 183.62 183.62 183.58 183.52 183.46 183.45 183.24 183.62 0.38
1994 183.39 183.32 183.28 183.30 183.40 183.46 183.53 183.56 183.59 183.56 183.50 183.42 183.44 183.28 183.59 0.31
1995 183.33 183.24 183.19 183.20 183.26 183.31 183.37 183.40 183.44 183.49 183.48 183.41 183.34 183.19 183.49 0.30
1996 183.34 183.32 183.30 183.31 183.46 183.60 183.70 183.78 183.78 183.71 183.67 183.63 183.55 183.30 183.78 0.48
1997 183.59 183.54 183.51 183.55 183.64 183.65 183.72 183.68 183.64 183.61 183.56 183.48 183.60 183.48 183.72 0.24
1998 183.40 183.34 183.29 183.35 183.34 183.39 183.41 183.38 183.33 183.26 183.21 183.19 183.32 183.19 183.41 0.22
1999 183.12 183.10 183.06 183.11 183.20 183.31 183.43 183.47 183.44 183.38 183.32 183.24 183.27 183.06 183.47 0.41
2000 183.16 183.08 183.08 183.12 183.16 183.24 183.33 183.31 183.27 183.20 183.15 183.06 183.18 183.06 183.33 0.27
2001 182.98 182.94 182.91 183.01 183.24 183.33 183.36 183.39 183.37 183.30 183.29 183.30 183.20 182.91 183.39 0.48
2002 183.22 183.14 183.11 183.14 183.26 183.31 183.36 183.40 183.42 183.44 183.36 183.26 183.29 183.11 183.44 0.33
2003 183.16 183.07 183.03 183.08 183.18 183.23 183.26 183.29 183.27 183.26 183.23 183.19 183.19 183.03 183.29 0.26
2004 183.14 183.07 183.07 183.13 183.23 183.35 183.40 183.42 183.46 183.47 183.46 183.38 183.30 183.07 183.47 0.40
2005 183.32 183.27 183.22 183.26 183.31 183.39 183.42 183.38 183.35 183.38 183.35 183.30 183.33 183.22 183.42 0.20
2006 183.24 183.18 183.12 183.16 183.24 183.30 183.31 183.30 183.20 183.13 183.04 182.98 183.18 182.98 183.31 0.33
2007 182.92 182.83 182.78 182.85 182.87 182.94 183.00 183.01 183.02 183.18 183.18 183.11 182.97 182.78 183.18 0.40
2008 183.08 183.03 182.97 183.01 183.18 183.29 183.41 183.42 183.37 183.32 183.27 183.19 183.21 182.97 183.42 0.45
2009 183.14 183.10 183.09 183.12 183.24 183.30 183.34 183.39 183.42 183.36 183.35 183.30 183.26 183.09 183.42 0.33
2010 183.21 183.14 183.09 183.08 183.08 183.13 183.19 183.20 183.22 183.19 183.14 183.07 183.15 183.07 183.22 0.15
2011 183.00 182.93 182.87 182.91 183.04 183.15 183.25 183.28 183.23 183.21 183.16 183.09 183.09 182.87 183.28 0.41
2012 183.01 182.94 182.93 183.00 183.06 183.20 183.30 183.27 183.20 183.13 183.11 183.06 183.10 182.93 183.30 0.37
2013 182.98 182.94 182.91 182.90 183.11 183.26 183.37 183.44 183.48 183.45 183.40 183.35 183.22 182.90 183.48 0.58
2014 183.29 183.24 183.23 183.27 183.47 183.60 183.66 183.67 183.70 183.71 183.67 183.60 183.51 183.23 183.71 0.48
2015 183.54 183.47 183.42 183.44 183.53 183.63 183.68 183.68 183.69 183.60 183.58 183.59 183.57 183.42 183.69 0.27
2016 183.55 183.49 183.46 183.48 183.50 183.61 183.69 183.70 183.70 183.68 183.59 183.54 183.58 183.46 183.70 0.24
2017 183.26 183.23 183.26 183.36 183.45 183.51 183.54 183.54 183.51 183.47 183.40 183.40 183.41 183.23 183.54 0.31
2018 183.65 183.58 183.54 183.47 183.50 183.56 183.65 183.65 183.70 183.77 183.76 183.67 183.63 183.47 183.77 0.30
2019 183.62 183.58 183.57 183.61 183.77 183.84 183.86 183.86 183.86 183.88 183.81 183.74 183.75 183.57 183.88 0.31
2020 183.71 183.64 183.57 183.62 183.64 183.70 183.76 183.81 183.79 183.76 183.71 183.63 183.70 183.67 183.81 0.24
2021 183.54 183.46 183.42 183.48 183.51 183.55 183.56 183.54 183.51 183.49 183.38 183.31 183.48 183.31 183.56 0.25
2022 183.24 183.17 183.15 183.24 183.44 183.57 183.62 183.65 183.65 183.60 183.60 183.57 183.46 183.15 183.65 0.50
2023 183.52 183.47 183.43 183.48 183.67 183.68 183.68 183.67 183.63 183.55 183.46 183.37 183.55 183.37 183.68 0.31
2024 183.32 183.26 183.21 183.24 183.33 183.44 183.52 183.48 183.45 183.34 183.3 183.25 183.35 183.21 183.52 0.31

All-time

Average 183.34 183.28 183.24 183.27 183.37 183.46 183.52 183.54 183.54 183.52 183.48 183.41 183.41 183.23 183.57 0.34
Minimum 182.83 182.76 182.74 182.72 182.76 182.85 182.96 183.01 183.02 183.10 183.01 182.92 182.94 182.72 183.16 0.15
Maximum 183.71 183.64 183.61 183.68 183.77 183.84 183.86 183.86 183.86 183.91 183.89 183.81 183.75 183.61 183.91 0.65

2015-2024

Average 183.52 183.46 183.42 183.45 183.55 183.63 183.68 183.68 183.68 183.65 183.60 183.54

Water levels in metres referred to Chart Datum

2024 0.12 0.06 0.01 0.04 0.13 0.24 0.32 0.28 0.25 0.14 0.10 0.05
All-Time
Average 0.14 0.08 0.04 0.07 0.17 0.26 0.32 0.34 0.34 0.32 0.28 0.21
Minimum -0.37 -0.44 -0.46 -0.48 -0.44 -0.35 -0.24 -0.19 -0.18 -0.10 -0.19 -0.28
Maximum 0.51 0.44 0.41 0.48 0.57 0.64 0.66 0.66 0.66 0.71 0.69 0.61
Date modified: