We think of lake-effect as winter snowfall, but lake-effect rain can fall in the summer. That can produce a little extra rainfall in some inland areas. Also, there is a “lake-shadow” where the lake can suppress rainfall in the summer near Lake Michigan. The average rainfall for Muskegon in July is 2.37″ and for Holland (Regional Airport) it’s 2.83″. Inland, the average July rainfall is 3.78″ for Grand Rapids and 3.70″ for Kalamazoo (30-year averages).
The top picture shows me playing golf yesterday at The Meadows at GVSU in Allendale in the PM. In the background you can see a beautiful cumulonimbus cloud, with the characteristic anvil-shaped top. While we stayed mostly sunny (in fact even no cumulus clouds much of the day) in Allendale with a NW wind off Lake Michigan, under this shower, there was some heavy rain:
This is Storm Total Rainfall off the Grand Rapids NWS radar for Saturday (8/18/18). There is some false return over Ottawa and Kent County, but note the line of rainfall from E. Allegan Co up thru Newaygo and Lake County, to Cadillac and east of Traverse City. Here the prevailing northeast wind met the lake-effect northwest wind. The result was a net convergence of air. Air was forced to rise and that updraft caused the showers. If Lake Michigan where not there, the showers would not be there. There were also lake effect showers in the Detroit area, as the prevailing wind met the lake breezes off Lakes Huron and Erie. Rainfall totaled 1.06″ at the gauge in Wayland, 0.08″ in Hopkins and 0.02″ in Alto. I’m sure some parts of NE Allegan Co. around Dorr had an inch of rain. When you forecast the weather in West Michigan, you have to consider the micro-climates that are produced in both summer and winter by Lake Michigan.