Michigan has a number of geographic features influencing the weather we experience. Lake effect snow is well documented and anyone who lives in the north can attest to the (relatively) mild summers along Grand Traverse bay. People in Grand Rapids experience snow flurries while Lanstronauts have power lines collapse.
Here is a visualization that looks at the timing or the extremes of weather. The coldest or warmest day is mapped out in bright colors. Data comes from the National Weather Service's daily normals. Location data from OpenStreetMap.