I have a pair of fleece lined tights, the fleece is very thin, but they are prteey warm in the 30's. If it's really cold, say in the mid 20's, I'll add regular sythetic long johns underneath. Never had a problem with them under the tights. Bu then again the rides won't be that long if it's that cold.

Your first pair of tights? Wait until you decide to stop at a store, like Walmart, while your wearing them. Or stop into a resturant with them on.