ARMY CORPS OF ENGINEERS WEEKLY GREAT LAKES WATER LEVEL UPDATE

ARMY CORPS OF ENGINEERS WEEKLY GREAT LAKES WATER LEVEL UPDATE > Apr 28, 2023

WEATHER CONDITIONS

Temperatures in the Great Lakes basin were below average over the past week with a slight warming to near average at the end of the work week. Most of the basin received some precipitation over the past week with Lakes Superior, Huron, Erie, and Ontario basins receiving about an inch of total precipitation and the Lake Michigan basin getting about a half inch of precipitation. Heading into the weekend, forecasts show temperatures falling below seasonal average conditions, except for near average temperatures in the far east including Syracuse and Rochester, NY. Forecasted temperatures appear to remain below average next week across the basin. Over the weekend, forecasts show precipitation across the northern and southeastern parts of the Great Lakes basin before dryer conditions return next week.

LAKE LEVEL CONDITIONS

Forecasted water levels for April 28th for Lakes Superior, Michigan-Huron, St. Clair, and Erie range from 3 to 6 inches above levels a month ago, while Lake Ontario is 10 inches above its level of a month ago. In addition, projected water levels for 28 April on Lakes Superior, Erie, and Ontario are above their levels from a year ago while levels on Lakes Michigan-Huron and St. Clair are 4 and 1 inches, respectively, below what they were a year ago. Projected levels for 28 April are above each lake’s respective April long-term average levels. Projected net change in levels on Lakes Superior, Michigan-Huron, and St. Clair by May 28th is to rise 1 to 3 inches, while Lake Erie is forecast to remain near its current level and Lake Ontario projected to climb 6 inches over the next 30 days. See our Daily Levels web page for more water level information.

FORECASTED MONTHLY OUTFLOWS/CHANNEL CONDITIONS

Lake Superior’s outflow through St. Marys River and Lake Michigan-Huron’s outflow through St. Clair River are forecasted to be above average for April. Lake St. Clair outflow through Detroit River, Lake Erie outflow through Niagara River, and Lake Ontario outflow through the St. Lawrence River are projected to be above average in April as well.

ALERTS

Water levels shown are still-water surface elevations over the entire lake surface. Water levels at specific locations may differ due to meteorological influences. Official records are based on monthly average water levels and not daily water levels. Great Lakes, connecting channels, and St. Lawrence River users should keep informed of current conditions before undertaking any activities affected by changing water levels. Mariners should use navigation charts and refer to current water level readings. Find ice information at National Ice Center’s website.