I thought someone might have posted about this, but I couldnt find it... Anyway, everytime it is humid, raining, or it cools off at night, my interior fogs up really bad. The worst part is the hatch glass, as the bottom half is completely white with fog and you cant see through it. The defogger helps, a little, with that. The windshield gets it pretty bad too, and I have to have a rag handy to wipe it down every 2-3 minutes. On dry days, or when the sun is out, it is perfect. It seems to worsen greatly if I have the windows closed. I have thought of the heater core, I had one go on a different car, but this isnt like that. In that car, only the front got fogged, and when wiped off it was very greasy and it reeked of antifreeze in the car. There is no actual "water" on the windows, and the windshield and hatch seals are good. Other than that, I have no idea. Any suggestions?