A strong storm system ripped through the Great Lakes basin this week, bringing more heavy rain, strong winds, and large waves on the lakes themselves. Many locations received more than 2 inches of rain Wednesday and wave heights on Lake Superior topped 14 feet. Much cooler air filtered into the region in the wake of the storm system. More showers are possible late Friday and into Saturday, before the sun returns on Sunday. To date in September, the Great Lakes basin as a whole has received almost double its average precipitation.
Water Level Conditions:
Lakes Superior and Michigan-Huron are 8 and 19 inches, respectively, above their levels of a year ago. Lakes St. Clair and Erie are 11 and 6 inches, respectively, above what they were at this time last year, while Lake Ontario is at the same level as a year ago. Lakes Superior and Michigan-Huron are both each predicted to fall an inch over the next month. Lakes St. Clair, Erie, and Ontario are projected to fall 4, 4, and 7 inches, respectively, over the next 30 days.
See the Great Lakes Water Levels web page for more water level information.
Forecasted outflows / channel conditions:
Lake Superiorís outflow through the St. Maryís River is forecasted to be well above average for the month of September. Lake Michigan-Huronís outflow into the St. Clair River and Lake St. Clairís outflow into the Detroit River are predicted to be near average in September. In addition, the outflow of Lake Erie into the Niagara River and Lake Ontarioís outflow into the St. Lawrence River are projected to be above average in September.
Official records are based on monthly average water levels and not daily water levels. Users of the Great Lakes, connecting channels and St. Lawrence River should keep informed of current conditions before undertaking any activities that could be affected by changing water levels. Mariners should utilize navigation charts and refer to current water level readings.