2021-Nov-15
November 14 Water Levels Report
The temperature throughout the basin has been above normal so far in November and is predicted to remain above normal through the coming week.
This month outflows from Lake Superior into the St. Mary’s River are predicted to be below average, not above average as they have been for almost 3 years prior to the spring of 2021. This shows that, under Plan 2012 balancing, the flow into Lake Michigan-Huron continues to be reduced. Lake Michigan-Huron continues to be below the level it was at this time last year – see first graph below. All the lakes are now lower than they were at this time last year.
From a month ago the water levels on Lakes Superior, Michigan-Huron & St Clair are down 5, 5, & 2 inches respectively and Lakes Erie and Ontario are up 0 & 3 inches respectively. Lakes Superior, Michigan-Huron, & St Clair are lower by 13, 17, & 6 inches, respectively, and Lakes Erie & Ontario are 0 & 9 inches higher, respectively, than they were at this time last year. Lakes Michigan-Huron, St Clair, Erie & Ontario are 15, 23, 26 & 12 inches, respectively, above their long term November average, whereas Lakes Superior is 3 inches below. All the lakes remain below their November record highs.
In a month’s time, the levels on all the Great Lakes are expected to be down 2 – 4 inches, with Lake Michigan-Huron down 2 inches.
Outflows from Lake Superior into the St. Mary’s River is predicted to be below average for this month and Lake Michigan-Huron’s outflow into the St. Clair River is predicted to be above average for this month. Lake St. Clair’s outflow through the Detroit River and Lake Erie’s outflow through the Niagara River are also forecasted to be above average in this month. In addition, Lake Ontario’s outflow through the St. Lawrence River is projected to be above average for this month.
This report below shows the most recent month of precipitation and outflows published by Level News:
With regard to the forecast graph below, and the more recently updated first graph in this report, the USACE is predicting that the most likely outcome is that the Lake Michigan-Huron level will continue its seasonal decline through December into February 2022, and then commence its seasonal rise in March 2022.
Monthly mean water levels for the previous year and the current year to date are shown as a solid line on the hydrographs. A projection for the next six months is given as a dashed line. This projection is based on the present condition of the lake basin and anticipated future weather. The shaded area shows a range of possible levels over the next six months dependent upon weather variations. Current and projected levels (solid and dashed lines) can be compared with the 1918-2019 average levels (dotted line) and extreme levels (shown as bars with their year of occurrence). The legend below further identifies the information on the hydrographs.
