Great Lakes Water Level Outlook - October 2018 Edition

Outlook Summary:

As of October 1st, all of the Great Lakes, except Lake Ontario, continue to experience water levels above their long-term average (LTA). This summer, which includes months June, July and August (JJA), was rather hot across the Great Lakes basin. Many places throughout the basin experienced a top 10 warmest summer based on average temperature over the 3 month time period. In the fall and winter months, air temperature and water temperature can have a large effect on evaporation, as cold air moves over the warm lakes, which can impact the total net basin supply to each of the lakes. Net Basin Supply (NBS) is the combined effect of precipitation over the lake, evaporation from the lake, and runoff to the lake. This edition of the Water Level Outlook incorporates the projection of water levels if NBS values are similar to those seen during the years when a hot summer was experienced in the Great Lakes basin followed by either a warm or cold October through December. The purple plume represents the range of water levels given the NBS scenarios of the hottest 14 summers occurred. The blue and red lines represent the NBS scenarios if a hot summer was followed by either a cold or warm October to December, respectively. The most recent coordinated 6-month forecast is also shown for comparison. Also, click on the link below to read the latest outlook, which also includes NBS scenarios of years a hurricane tracked similar to Hurricane Florence that occurred in mid-September.

 

 

 





Click on the individual graphics to view a larger, printer-friendly image (pdf).


















* At this time, water level outlooks for Lake Ontario are still under development due to complexities of its weekly regulation process.






Click here to obtain the full Great Lakes Water Level Outlook document (pdf)

Great Lakes Water Level Outlook Data

 

To view the water level outlook data in tabular format, click on the links below.

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Lake Superior

Monthly Mean Water Level (meters IGLD)
Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19
Maximum Hot Summer Scenario 183.69 183.62 183.58 183.55 183.57 183.67 183.85 183.93 183.95 183.93 183.90 183.85
Minimum Hot Summer Scenario 183.65 183.53 183.43 183.39 183.38 183.44 183.48 183.50 183.51 183.47 183.38 183.31
1955 183.67 183.57 183.48 183.40 183.38 183.46 183.55 183.61 183.64 183.62 183.56 183.49
1983 183.66 183.56 183.51 183.48 183.50 183.55 183.65 183.73 183.75 183.74 183.71 183.66
1995 183.68 183.62 183.58 183.55 183.57 183.67 183.79 183.88 183.92 183.90 183.87 183.82
2006 183.68 183.58 183.47 183.40 183.42 183.44 183.48 183.53 183.51 183.51 183.59 183.61
2016 183.68 183.60 183.55 183.52 183.55 183.66 183.77 183.82 183.86 183.90 183.90 183.84
Long Term Average 183.40 183.33 183.26 183.23 183.26 183.36 183.45 183.51 183.54 183.54 183.51 183.47
Long Term Maximum 183.81 183.70 183.63 183.61 183.68 183.74 183.76 183.82 183.86 183.86 183.91 183.89
Long Term Minimum 182.92 182.83 182.76 182.74 182.72 182.76 182.85 182.96 183.01 183.02 183.10 183.01

Lake Michigan-Huron

Monthly Mean Water Level (meters IGLD)
Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19
Maximum Hot Summer Scenario 176.85 176.86 176.83 176.84 176.94 177.10 177.25 177.31 177.31 177.25 177.19 177.14
Minimum Hot Summer Scenario 176.79 176.69 176.61 176.59 176.65 176.73 176.80 176.83 176.78 176.71 176.62 176.59
1955 176.79 176.72 176.68 176.67 176.72 176.82 176.90 176.93 176.94 176.88 176.77 176.68
1983 176.81 176.76 176.75 176.78 176.84 176.92 177.00 177.04 177.02 176.98 176.95 176.92
1995 176.80 176.77 176.79 176.78 176.85 177.00 177.13 177.21 177.22 177.21 177.19 177.14
2006 176.85 176.86 176.82 176.81 176.87 176.91 176.91 176.89 176.85 176.77 176.68 176.59
2016 176.80 176.76 176.79 176.83 176.94 177.09 177.21 177.27 177.25 177.18 177.14 177.12
Long Term Average 176.33 176.30 176.28 176.30 176.38 176.48 176.55 176.58 176.56 176.51 176.44 176.38
Long Term Maximum 177.26 177.18 177.11 177.12 177.23 177.28 177.33 177.39 177.39 177.38 177.50 177.38
Long Term Minimum 175.61 175.57 175.59 175.58 175.61 175.74 175.76 175.78 175.77 175.76 175.70 175.65

Lake St. Clair

Monthly Mean Water Level (meters IGLD)
Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19
Maximum Hot Summer Scenario 175.54 175.60 175.62 175.70 175.82 175.86 175.90 175.86 175.81 175.74 175.70 175.65
Minimum Hot Summer Scenario 175.44 175.31 175.23 175.31 175.37 175.46 175.39 175.35 175.30 175.22 175.17 175.17
1955 175.44 175.31 175.23 175.37 175.48 175.68 175.66 175.62 175.62 175.54 175.39 175.26
1983 175.53 175.45 175.51 175.60 175.61 175.66 175.71 175.67 175.61 175.56 175.49 175.44
1995 175.45 175.40 175.44 175.44 175.52 175.66 175.78 175.79 175.73 175.74 175.70 175.65
2006 175.54 175.60 175.54 175.58 175.62 175.61 175.55 175.48 175.45 175.37 175.26 175.17
2016 175.49 175.50 175.52 175.57 175.64 175.75 175.84 175.80 175.75 175.66 175.61 175.64
Long Term Average 174.91 174.84 174.79 174.90 175.04 175.13 175.18 175.20 175.16 175.09 175.00 174.91
Long Term Maximum 175.80 175.80 175.80 175.80 175.82 175.83 175.92 175.93 175.90 175.84 175.96 175.82
Long Term Minimum 174.24 173.88 173.89 174.05 174.32 174.42 174.45 174.50 174.41 174.34 174.27 174.18

Lake Erie

Monthly Mean Water Level (meters IGLD)
Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19
Maximum Hot Summer Scenario 174.67 174.78 174.89 174.96 175.07 175.13 175.17 175.05 174.93 174.83 174.79 174.80
Minimum Hot Summer Scenario 174.58 174.45 174.38 174.47 174.53 174.60 174.52 174.45 174.39 174.28 174.21 174.21
1955 174.58 174.45 174.38 174.52 174.69 174.84 174.89 174.81 174.77 174.66 174.50 174.36
1983 174.65 174.65 174.67 174.79 174.86 174.92 174.93 174.85 174.75 174.67 174.57 174.49
1995 174.58 174.55 174.55 174.59 174.68 174.80 174.93 174.95 174.85 174.79 174.75 174.70
2006 174.67 174.78 174.77 174.78 174.86 174.83 174.74 174.64 174.60 174.54 174.39 174.29
2016 174.61 174.67 174.73 174.76 174.85 174.99 175.03 174.99 174.93 174.80 174.65 174.65
Long Term Average 173.99 174.00 173.99 174.08 174.23 174.31 174.34 174.33 174.26 174.17 174.07 174.00
Long Term Maximum 174.89 174.86 174.78 174.88 174.98 174.97 175.04 175.03 174.94 174.83 174.94 174.85
Long Term Minimum 173.19 173.21 173.18 173.20 173.38 173.44 173.45 173.45 173.43 173.38 173.30 173.20

Lake Superior

Monthly Mean Water Level (ft IGLD)
Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19
Maximum Hot Summer Scenario 602.65 602.42 602.30 602.19 602.26 602.61 603.17 603.44 603.53 603.44 603.33 603.19
Minimum Hot Summer Scenario 602.54 602.14 601.79 601.66 601.62 601.85 601.98 602.04 602.06 601.94 601.64 601.40
1955 602.58 602.27 601.98 601.69 601.62 601.90 602.20 602.40 602.50 602.42 602.23 602.00
1983 602.57 602.24 602.05 601.96 602.02 602.21 602.53 602.80 602.85 602.82 602.71 602.55
1995 602.62 602.42 602.30 602.19 602.26 602.61 602.97 603.27 603.41 603.35 603.26 603.10
2006 602.62 602.30 601.93 601.72 601.76 601.85 601.98 602.12 602.06 602.05 602.34 602.40
2016 602.62 602.36 602.21 602.08 602.19 602.57 602.91 603.09 603.22 603.33 603.33 603.15
Long Term Average 601.71 601.48 601.25 601.15 601.25 601.57 601.87 602.07 602.17 602.17 602.07 601.94
Long Term Maximum 603.05 602.69 602.46 602.40 602.62 602.82 602.89 603.08 603.22 603.22 603.38 603.31
Long Term Minimum 600.13 599.84 599.61 599.54 599.48 599.61 599.90 600.26 600.43 600.46 600.72 600.43

Lake Michigan-Huron

Monthly Mean Water Level (ft IGLD)
Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19
Maximum Hot Summer Scenario 580.23 580.26 580.15 580.18 580.53 581.03 581.52 581.72 581.72 581.52 581.34 581.15
Minimum Hot Summer Scenario 580.02 579.71 579.43 579.37 579.55 579.82 580.04 580.14 579.99 579.76 579.47 579.36
1955 580.02 579.78 579.64 579.61 579.78 580.12 580.37 580.47 580.52 580.33 579.97 579.66
1983 580.09 579.92 579.90 580.00 580.18 580.45 580.72 580.84 580.77 580.65 580.53 580.44
1995 580.05 579.96 580.03 580.00 580.21 580.71 581.14 581.41 581.42 581.39 581.34 581.15
2006 580.23 580.26 580.12 580.08 580.29 580.43 580.42 580.35 580.20 579.95 579.67 579.36
2016 580.05 579.93 580.01 580.16 580.53 581.01 581.39 581.60 581.52 581.30 581.18 581.09
Long Term Average 578.51 578.41 578.35 578.41 578.67 579.00 579.23 579.33 579.27 579.10 578.87 578.67
Long Term Maximum 581.56 581.30 581.07 581.10 581.46 581.63 581.79 581.99 581.99 581.96 582.35 581.96
Long Term Minimum 576.15 576.02 576.08 576.05 576.15 576.57 576.64 576.71 576.67 576.64 576.44 576.28

Lake St. Clair

Monthly Mean Water Level (ft IGLD)
Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19
Maximum Hot Summer Scenario 575.91 576.10 576.19 576.43 576.84 576.98 577.12 576.97 576.80 576.56 576.45 576.27
Minimum Hot Summer Scenario 575.59 575.16 574.91 575.17 575.37 575.66 575.44 575.31 575.14 574.89 574.70 574.71
1955 575.59 575.16 574.91 575.36 575.73 576.37 576.30 576.17 576.17 575.91 575.43 574.99
1983 575.87 575.61 575.83 576.12 576.15 576.30 576.49 576.34 576.15 575.97 575.76 575.59
1995 575.64 575.47 575.58 575.59 575.84 576.30 576.71 576.74 576.55 576.56 576.45 576.27
2006 575.91 576.10 575.90 576.05 576.18 576.16 575.96 575.72 575.62 575.37 575.00 574.71
2016 575.76 575.80 575.87 576.01 576.24 576.61 576.89 576.76 576.59 576.31 576.14 576.25
Long Term Average 573.85 573.62 573.46 573.82 574.28 574.57 574.74 574.80 574.67 574.44 574.15 573.85
Long Term Maximum 576.77 576.77 576.77 576.77 576.84 576.87 577.17 577.20 577.10 576.90 577.30 576.84
Long Term Minimum 571.65 570.47 570.51 571.03 571.92 572.24 572.34 572.51 572.21 571.98 571.75 571.46

Lake Erie

Monthly Mean Water Level (ft IGLD)
Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19
Maximum Hot Summer Scenario 573.06 573.43 573.77 574.03 574.39 574.57 574.70 574.33 573.93 573.59 573.45 573.48
Minimum Hot Summer Scenario 572.76 572.35 572.11 572.40 572.61 572.84 572.56 572.33 572.13 571.80 571.55 571.55
1955 572.78 572.35 572.11 572.56 573.12 573.62 573.78 573.54 573.38 573.02 572.50 572.04
1983 573.01 573.00 573.07 573.46 573.70 573.88 573.93 573.67 573.34 573.06 572.74 572.47
1995 572.76 572.68 572.68 572.81 573.09 573.50 573.92 573.99 573.64 573.47 573.32 573.15
2006 573.06 573.43 573.39 573.42 573.69 573.59 573.29 572.95 572.85 572.64 572.14 571.83
2016 572.85 573.06 573.26 573.35 573.66 574.11 574.24 574.11 573.92 573.49 573.01 573.00
Long Term Average 570.83 570.87 570.83 571.13 571.62 571.88 571.98 571.95 571.72 571.42 571.10 570.87
Long Term Maximum 573.79 573.69 573.43 573.75 574.08 574.05 574.28 574.25 573.95 573.59 573.95 573.65
Long Term Minimum 568.21 568.27 568.18 568.24 568.83 569.03 569.06 569.06 569.00 568.83 568.57 568.24

Detroit District Disclaimer

NOTICE: All data contained herein is preliminary in nature and therefore subject to change. The data is for general information purposes ONLY and SHALL NOT be used in technical applications such as, but not limited to, studies or designs. All critical data should be obtained from and verified by the United States Army Corps of Engineers, Detroit District, Engineering and Technical Services, Great Lakes Hydraulics and Hydrology Office, 477 Michigan Ave., Detroit, MI 48226. The United States of America assumes no liability for the completeness or accuracy of the data contained herein and any use of such data inconsistent with this disclaimer shall be solely at the risk of the user.