The thing is Michigan is a cold state so Temp departures and snow don't go hand in hand as they would in, say, the mid Atlantic. Northern Michigan can have a banner snow year with way above avg Temps. Likewise a bitter cold winter can freeze the lakes early and shut off the lake effect machine prematurely leaving to well below normal snow. I've studied a ton of climatology for Detroit and even in the "warmest" and" least snowy" part of the state, there is no direct correlation with temperatures and snowfall. Once you get to the North country, it's an absolute crap shoot. And what I mean by correlation, is that everything is basically dependent on weather patterns and storm tracks.