I have noticed lately that the morning after a cold night, there is frost lining the insides of the windows on my 2001 XJ. Is this normal? Or does this mean that moisture is somehow getting inside the jeep? I know that cherokees are known to have the floors and rockers rust out, so I want to make sure it is not going to encourage anything to rust out and lead to expensive repairs in the future. Thanks in advance for any input guys.

 

I'm not 100% but I think your carpet is wet and blasting the heat makes moister and I don't think there is much you can do until they dry. But at least they are drying.