If you end up here in Tucson, I don't feel like fenders are totally essential... I don't have them on my commuter (my Trek 7.2 FX) because when it rains, it basically either isn't that big of a deal or is SO torrential that I wouldn't feel safe riding in it (i.e. monsoon).
That was my thought about ending up in Tucson--no fenders necessary! Most of the schools I'm applying to are in Indiana or Ohio, though, so it does really depend where I end up.