Water on INSIDE of windshield.... now carpets wet!

[The dude]

I had the box sitting on the driveway in late fall until I had the garage cleaned up to put the car to sleep for winter time. I noticed the inside of the window would be wet on cold days. I have never seen a car do this. Is this something to do with it being a convertible? I don't get it.

The car has smelled musty the last few days and today I went to start it up as it has not been run in the last 3 months. I was spraying febreeze on the carpet and when I lefted the floor mats, the carpet was wet. I moved the seat forward and it was drenched behind the seat. I reached under the seat and there was probably 1 inch of water.

What the heck is going on! Also, I should mention, I had all the drain holes cleaned this summer and fall, I doubt it is that!