US Army Corps of Engineers
Detroit District Website

Quick Links

Redirecting...

Great Lakes Water Level Future Scenarios - April Scenarios

Water Level Scenarios Summary:

This product is not an official forecast of Great Lakes water levels. Rather, this product is meant to illustrate outcomes that would occur under historical weather and water supply condition, with scenarios chosen based on similarities to recent conditions. For the official forecast, please see our Monthly Bulletin of Great Lakes Water Levels. This tool has been predominantly used to show the possible range of water levels in the upcoming year based on historical hydrologic conditions and water supplies. Beginning in 2021, we will be modifying our scenarios to account for different time periods based on the scenario that is chosen. 

 

Water levels follow a seasonal cycle where water levels rise in the spring due to increased precipitation and enhanced runoff from snowmelt. In the fall, the lakes generally decline due to an increase in evaporation as temperatures decline and cold air moves over the relatively warm lake waters. We refer to the combined effect of precipitation over the lake, evaporation from the lake, and runoff to the lake as Net Basin Supply (NBS). This edition of the Water Level Future Scenarios showcases a purple plume that represents ten years of the lowest NBS from January to March for the Great Lakes basin, which has been similar to 2021. Two of the years within the plume have been called out to show the difference in hydroclimate conditions that could occur over the next 12 months.  The most recent coordinated 6-month forecast is also shown for comparison.



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


12-Month Outlook Legend

 
Lake Superior 12-Month Outlook Graphic Lakes Michigan-Huron 12-Month Outlook Graphic
Lake St. Clair 12-Month Outlook Graphic Lake Erie 12-Month Outlook Graphic


12-Month Outlook Legend
 
 
* For the official 6-month forecast of all lakes, including Lake Ontario, see the Monthly Bulletin of Great Lakes Water Levels.
 

 

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

Great Lakes Water Level Future Scenarios Data

Collapse All Expand All

Lake Superior

Monthly Mean Water Level (meters IGLD)

  Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-21 Oct-21 Nov-21 Dec-21 Jan-22 Feb-22 Mar-22
Maximum Low Jan-Mar NBS. 183.49 183.62 183.75 183.78 183.79 183.82 183.81 183.77 183.69 183.61 183.54 183.52
Minimum Low Jan-Mar NBS 183.41 183.40 183.45 183.49 183.49 183.50 183.43 183.37 183.31 183.23 183.17 183.11
1987-88 183.42 183.44 183.47 183.51 183.54 183.50 183.43 183.37 183.31 183.24 183.17 183.13
2015-16 183.45 183.54 183.64 183.70 183.73 183.73 183.67 183.62 183.62 183.59 183.54 183.52
Long Term Average 183.27 183.37 183.45 183.52 183.54 183.54 183.52 183.48 183.41 183.33 183.27 183.24
Long Term Maximum 183.68 183.77 183.84 183.86 183.86 183.86 183.91 183.89 183.81 183.71 183.64 183.61
Long Term Minimum 182.72 182.76 182.85 182.96 183.01 183.02 183.10 183.01 182.92 182.83 182.76 182.74

 

Lake Michigan-Huron

Monthly Mean Water Level (meters IGLD)

 

  Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-21 Oct-21 Nov-21 Dec-21 Jan-22 Feb-22 Mar-22
Maximum Low Jan-Mar NBS. 177.00 177.06 177.12 177.16 177.16 177.12 177.04 176.98 176.96 176.92 176.90 176.97
Minimum Low Jan-Mar NBS 176.95 176.94 176.92 176.92 176.88 176.82 176.75 176.64 176.54 176.46 176.44 176.45
1987-88 176.97 176.97 176.97 176.94 176.89 176.85 176.76 176.67 176.64 176.61 176.57 176.56
2015-16 177.00 177.06 177.12 177.14 177.11 177.06 176.97 176.89 176.91 176.92 176.90 176.97
Long Term Average 176.40 176.50 176.57 176.60 176.58 176.53 176.46 176.40 176.36 176.31 176.30 176.32
Long Term Maximum 177.30 177.38 177.45 177.46 177.42 177.38 177.50 177.38 177.26 177.26 177.25 177.22
Long Term Minimum 175.61 175.74 175.76 175.78 175.77 175.76 175.70 175.65 175.61 175.57 175.59 175.58

 

Lake St. Clair

Monthly Mean Water Level (meters IGLD)

 

  Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-21 Oct-21 Nov-21 Dec-21 Jan-22 Feb-22 Mar-22
Maximum Low Jan-Mar NBS. 175.60 175.68 175.82 175.87 175.79 175.70 175.56 175.48 175.49 175.50 175.51 175.63
Minimum Low Jan-Mar NBS 175.48 175.51 175.50 175.50 175.42 175.36 175.31 175.21 175.18 175.11 175.15 175.17
1987-88 175.55 175.54 175.53 175.51 175.47 175.42 175.33 175.26 175.30 175.22 175.19 175.25
2015-16 175.60 175.68 175.82 175.87 175.79 175.70 175.56 175.48 175.47 175.50 175.51 175.63
Long Term Average 175.06 175.15 175.20 175.22 175.18 175.11 175.02 174.93 174.93 174.86 174.81 174.93
Long Term Maximum 175.91 175.98 176.02 176.04 175.97 175.88 175.96 175.82 175.80 175.80 175.80 175.83
Long Term Minimum 174.32 174.42 174.45 174.50 174.41 174.34 174.27 174.18 174.24 173.88 173.89 174.05

 

Lake Erie

Monthly Mean Water Level (meters IGLD)

 

  Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-21 Oct-21 Nov-21 Dec-21 Jan-22 Feb-22 Mar-22
Maximum Low Jan-Mar NBS. 174.71 174.83 174.96 175.05 174.95 174.82 174.67 174.54 174.57 174.60 174.57 174.70
Minimum Low Jan-Mar NBS 174.63 174.65 174.63 174.60 174.52 174.39 174.31 174.29 174.28 174.26 174.32 174.37
1987-88 174.65 174.68 174.68 174.66 174.61 174.54 174.45 174.36 174.37 174.37 174.36 174.39
2015-16 174.67 174.79 174.96 175.05 174.95 174.82 174.67 174.54 174.53 174.54 174.57 174.70
Long Term Average 174.24 174.33 174.36 174.34 174.28 174.19 174.09 174.02 174.01 174.02 174.01 174.10
Long Term Maximum 175.05 175.08 175.14 175.13 175.02 174.87 174.94 174.85 174.89 174.86 174.90 174.95
Long Term Minimum 173.38 173.44 173.45 173.45 173.43 173.38 173.30 173.20 173.19 173.21 173.18 173.20

 

Lake Superior

Monthly Mean Water Level (ft IGLD)

  Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-21 Oct-21 Nov-21 Dec-21 Jan-22 Feb-22 Mar-22
Maximum Low Jan-Mar NBS. 602.00 602.44 602.84 602.95 603.00 603.07 603.05 602.92 602.65 602.38 602.16 602.10
Minimum Low Jan-Mar NBS 601.72 601.69 601.86 601.99 602.00 602.05 601.80 601.60 601.42 601.15 600.94 600.75
1987-88 601.76 601.84 601.94 602.07 602.16 602.05 601.80 601.60 601.43 601.19 600.94 600.82
2015-16 601.86 602.15 602.49 602.70 602.79 602.77 602.60 602.43 602.42 602.32 602.16 602.10
Long Term Average 601.28 601.61 601.87 602.10 602.17 602.17 602.10 601.97 601.74 601.48 601.28 601.18
Long Term Maximum 602.62 602.92 603.15 603.22 603.22 603.22 603.38 603.31 603.05 602.72 602.49 602.40
Long Term Minimum 599.48 599.61 599.90 600.26 600.43 600.46 600.72 600.43 600.13 599.84 599.61 599.54

 

Lake Michigan-Huron

Monthly Mean Water Level (ft IGLD)

 

  Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-21 Oct-21 Nov-21 Dec-21 Jan-22 Feb-22 Mar-22
Maximum Low Jan-Mar NBS. 580.72 580.91 581.11 581.23 581.22 581.12 580.84 580.64 580.57 580.44 580.37 580.61
Minimum Low Jan-Mar NBS 580.56 580.51 580.45 580.45 580.30 580.13 579.88 579.54 579.20 578.94 578.86 578.90
1987-88 580.60 580.61 580.61 580.51 580.36 580.22 579.92 579.61 579.53 579.44 579.31 579.26
2015-16 580.69 580.91 581.11 581.17 581.06 580.91 580.61 580.35 580.41 580.44 580.37 580.61
Long Term Average 578.74 579.07 579.30 579.40 579.33 579.17 578.94 578.74 578.61 578.44 578.41 578.48
Long Term Maximum 581.69 581.96 582.19 582.22 582.09 581.96 582.35 581.96 581.56 581.56 581.53 581.43
Long Term Minimum 576.15 576.57 576.64 576.71 576.67 576.64 576.44 576.28 576.15 576.02 576.08 576.05

 

Lake St. Clair

Monthly Mean Water Level (ft IGLD)

 

  Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-21 Oct-21 Nov-21 Dec-21 Jan-22 Feb-22 Mar-22
Maximum Low Jan-Mar NBS. 576.11 576.37 576.82 577.00 576.75 576.44 575.99 575.71 575.75 575.78 575.83 576.20
Minimum Low Jan-Mar NBS 575.73 575.82 575.80 575.79 575.52 575.33 575.15 574.82 574.73 574.50 574.65 574.72
1987-88 575.96 575.92 575.89 575.83 575.68 575.52 575.24 575.01 575.13 574.88 574.77 574.95
2015-16 576.11 576.37 576.82 577.00 576.75 576.44 575.99 575.71 575.70 575.78 575.83 576.20
Long Term Average 574.34 574.64 574.80 574.87 574.74 574.51 574.21 573.92 573.92 573.69 573.52 573.92
Long Term Maximum 577.13 577.36 577.49 577.56 577.33 577.03 577.30 576.84 576.77 576.77 576.77 576.87
Long Term Minimum 571.92 572.24 572.34 572.51 572.21 571.98 571.75 571.46 571.65 570.47 570.51 571.03

 

Lake Erie

Monthly Mean Water Level (ft IGLD)

 

  Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-21 Oct-21 Nov-21 Dec-21 Jan-22 Feb-22 Mar-22
Maximum Low Jan-Mar NBS. 573.20 573.59 574.01 574.31 573.98 573.55 573.05 572.64 572.73 572.84 572.75 573.15
Minimum Low Jan-Mar NBS 572.93 572.99 572.95 572.84 572.57 572.15 571.88 571.81 571.78 571.72 571.92 572.08
1987-88 573.00 573.11 573.08 573.04 572.87 572.64 572.33 572.05 572.07 572.09 572.04 572.16
2015-16 573.08 573.47 574.01 574.31 573.98 573.55 573.05 572.64 572.60 572.65 572.75 573.15
Long Term Average 571.65 571.95 572.05 571.98 571.78 571.49 571.16 570.93 570.90 570.93 570.90 571.19
Long Term Maximum 574.31 574.41 574.61 574.57 574.21 573.72 573.95 573.65 573.79 573.69 573.82 573.98
Long Term Minimum 568.83 569.03 569.06 569.06 569.00 568.83 568.57 568.24 568.21 568.27 568.18 568.24

 

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.