What's New Great Lakes levels high as spring begins Green Bay Press-Gazette (3/21) An early freeze this winter season helped set the stage for major ice coverage of the Great Lakes, usually a good sign that water levels will remain high for most of the year.
Lake-level plan lacks top-level endorsements Rochester Democrat and Chronicle (2/19) Lake Ontario may be nearly frozen over, but fevers still run high along the shoreline as folks continue to debate the merit of changing the way the lake's water levels are regulated.
Last week was warm and dry across the majority of the Great Lakes basin. Temperatures for the week ranged from 2° to 6°F above normal in the eastern portion to over 15°F above normal in parts of the northwestern portion of the basin. As a result, a large amount of the snowpack has melted, especially in the Lake Michigan, Lake St. Clair, and Lake Erie basins where little snow now remains. Despite the warm past week, the mean temperature for March to date remained below normal across the majority of the basin. The forecast calls for 0.1 to 0.5 inches of precipitation in the northern portion of the basin and 0.5 to 1 inch of precipitation in the southern portion, with the likelihood of precipitation highest Friday through Saturday, especially in the southeastern portion of the basin. Temperatures are forecast to drop to below normal over the weekend, with highs ranging from the low thirties to the mid fifties, but return to normal or above normal temperatures by Wednesday.
Lake Level Conditions:
Lakes Superior and Michigan-Huron are 8 and 22 inches, respectively, above what they were at this time last year. Lake St. Clair is 10 inches above last year’s level. Lake Erie is at the same level of a year ago, and Lake Ontario is 6 inches below its level of a year ago. Lake Superior is predicted to rise one inch over the next 30 days, while Lake Michigan-Huron is expected to rise 3 inches. Lakes St. Clair, Erie, and Ontario are forecasted to rise 5, 9, and 10 inches, respectively over the next month. Ice jams remain a challenge to forecasting in the connecting channels, especially the St. Clair River. Water levels may fluctuate significantly while ice is present. See the Daily Levels page for more water level information.
Forecasted outflows / channel conditions:
Lake Superior’s outflow through the St. Mary’s River is forecasted to be above average for the month of March. Lake Michigan-Huron’s outflow into the St. Clair River and Lake St. Clair’s outflow into the Detroit River are predicted to be above average in March. In addition, the outflow of Lake Erie into the Niagara River and Lake Ontario’s outflow into the St. Lawrence River are predicted to be near average in March.
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.
Ice information can be found at the National Ice Center's webpage.