For me, since I've been in Michigan, I know that it's spring when I can drive my car with the windows rolled down and laugh at the children who are wearing short skirts and belly shirts and then when it's cold and snowing the next day, I can laugh at the same children who are absent from school because they have a cold. They must have forgotten that the weather in Michigan changes every 5 minutes or so.
When I was growing up in Mississippi, it was spring when you had to turn on your air conditioner because it was just that hot. Also, it was spring when you saw men walking down the street with no shirt on and plus sized women wearing junior sized sundresses.
In either place, it's spring for me when Payless has the buy one, get one 1/2 off summer sale!!! More sandals!!!!