Great Lakes Water Levels/Beach Water Temps. Compared to Last YearJuly 6th, 2013 at 12:18 am by Bill Steffen under Bill's Blog, Weather
Here’s a county map of the Lake Michigan Drainage Basin from USGS. Click here to enlarge. Note how little of the rain that falls across far southern Wisconsin, northern Illnois and NW Indiana actually gets into Lake Michigan. The rest drains away to the Mississippi River. The city of Chicago is allowed to remove 3200 cubic feet per second of water from the Great Lakes system. Half of this, 1 billion US gallons a day, is sent down the Chicago River, while the rest is used for drinking water. By comparison, the mean flow on the Grand River in Grand Rapids on 7/6 is 2730 cubic feet per second. Right now the volume of water in our area rivers is generally above average. The current flow on the Grand River in G.R. as I type this is 3720 cfs. Lake Michigan/Huron held steady last week. It’s up 3″ in the past month and is now 1″ higher than last year on 7/5. The lake is still 19″ below the July historical average, but 12″ above the lowest level for July set back in 1964. Lake Superior is also up 3″ in the last month and is also 1″ above the level of one year ago. Lake Erie gained 1″ in the last week and 5″ in the last month. It’s 4″ above the level of one year ago and 7″ below the historical average. Lake Ontario has gained 7″ in the last month and is now a whopping 13″ higher than it was one year ago. Ontario is 7″ ABOVE the historical average.
Also, Great Lakes water temperatures are cooler than the last couple years. The water temperature at Grand Haven on Friday was 58. Last year on July 5th, the water temperature at Grand Haven was 75. At Muskegon it was 62 on Friday and 74 one year ago (July 5). Pentwater reported a water temp. of 60 on Friday. One year ago the water at Pentwater was 73 degrees. The mid-Lake Michigan buoy showed a water temperature of 61.0 at 8 AM Friday. One year ago the water temp. on July 5 was 74.7. In 2011 on July 6th, the water temperature was 73 at Holland, Saugatuck and S. Haven and 74 at Grand Haven.