I have the same problem in my passenger side headlight and turn signal covers....all fogged and with water droplets.....used to go away after a day or 2 now its hanging around for over a week with no end in sight....someone mentioned on another thread to remove the back cover for a night or 2 and drive around ......I might try that but I would really like to know whats causing the problem in the first place !!
heres the message
I was having the same issue for a week, there a few threads on here that deal with the same issue. So I thought I'd have to reseal the headlight housing or even buy a new headlight housing back plate but it turns out that if you remove the back on the headlight housing and drive around (this will clear the condensation out) and put the back plate back on you shouldn't have this issue again.
I basically used this approach and have been issue free since October. If it continues try replacing the back plate cover on the headlight unit first before removing the headlight and resealing with caulking.