30-32 degrees is pretty darn warm for a winter snowboard day, *especially* if the sun is shining.
If it were me (and I am usually the one who feels chilly when i go places) I would wear:
-Under Armour (or similar) base layer on torso and legs
-light weight (or nothing) mid layer on torso... a long sleeve, thin polyester shirt or similar
-no mid layer on legs
-Snowboarding shell pants and jacket (10K or 15K)
You might be a little chilly on the lift (especially if it is windy), but you'll be sweating when you hit the slopes (unless you fall down all the time and sit around). Wisconsin doesn't have any huge mountains, so the temperature at the top will still be close to 30º (and warm for a winter ski day)