@ Rinkle

I too live in the south and are experiencing the same issue you have encountered. Regardless of science posted above every other vehicle I have owned or operated in this location has never had this issue to this extreme. Generally speaking our temperature shifts are not that different from day/night. Maybe 10-15 deg differential. It has happened twice in the 9 months of ownership. It is usually a hard rain.

If your experience was like mine, the quantity of water may have been somewhat understated in your post. I was shocked at the amount of water and am concerned about long term moisture effects on the dash electronics and fit/finish.

We had a storm this weekend and it occurred again, I confirmed the vent was set to pull air from the outside. The front windshield was totally saturated, the front driver/pax windows had a considerable amount. All rear windows had NO noticeable buildup. I would expect if a temp shift condensation occurred it would be on ALL windows? It left me with zero visibility from the front requiring a wipe down. I am going to try to leave it on cabin circulate to see if it occurs again.

Pending on results it could be some unsealed area or poor water vapor barrier in the firewall perhaps?

Please PM me should anyone locate any confirmed fixes. Thanks!

 

I have a 2011 Sonata and I have the same problem there is always moisture on the inside of the car and I took it in and they said they can't find a problem. I am getting tired of it.

 

We've had some pretty dramatic temperature swings lately although humidity has been seemingly lower. Since Ive kept the A/C on Recirculate I have not experienced the issue again.