A friend just sent this tip to me via my email. It's a good one and I'll add it here for you to try at your leisure.
As most RV'rs know, the windows inside your RV will steam up on cold or cold and damp days. There's lots of reasons for this and other publications discuss why this happens at length. That isn't what this article is about, I only intend to offer a tip about how to prevent it.
The friend that sent this tip was recently RVing along the southern Oregon Coast and finally complained out loud to her husband about the steamed up and wet windows of their RV. Her husband used to be a commercial fisherman and used this tip all the time to keep the glass clear on the boat. The area he fished was out of the north Oregon and southern Washington Coast near the mouth of the Columbia River. The weather there can be extreme!
When he heard the complaint he said, "Why don't you just coat the windows with dish soap? That's what we used to do on the boat! It works great." Later she asked him why he hadn't told her about that before, his answer; "Well! you never complained about it before!"