Michigan inland, Great Lakes water temperatures. Where it's warmest

After a week of temperatures in the upper 40s across the UP and mid 80s farther south, Michigan's Great Lakes and inland waters are starting to cool as fall approaches, according to recorded temperatures across the region.

Water temperatures in the Great Lakes peak in the late summer and early fall, according to GLISA , a collaborative between Michigan State University, University of Michigan and the National Oceanic and Atmospheric Administration .