Well this weekend we had rain like the world was coming to an end

Drove the car on the Motorway at 55 in the first lane, as you just couldn't see enough to drive faster safely (although many were). Luckily my wipers were fine and not smearing, just sheer volume of water.
When the wife and I went back out about an hour or so later, as soon as we got in the car, it misted up completely. Now we were in dry cloths (not damp), and the rubber mats had the lightest bit of moisture on them from getting in the car. To be fair put the aircon on, and within seconds, the windscreen was clear, but as soon as I turned the AC off, it started misting again. Checked the car when we got home (under the mats, seats, boot etc), and no damp patches anywhere, so don't think there's a leak in the car. My Scirocco used to mist up, but not as badly or quickly as the GTD did on Saturday night. Anyone else experience this ?
Checked again on the Sunday (whilst I was cleaning the car), and sure enough it was bone dry inside, and when I drove it later, no signs of misting ?