We do have a similar problem during monsoon season in AZ. Yes we have a big time wet season from the beginning on July to the middle of Sept. What people do that leave their RVs here in the summer is leave the AC on at 80 degrees. If you don't have power you have to use a moisture removal product that can be found at any local RV supply store. Don't just close the door and walk away, you may be very sorry when you return. Also try to arrange for a local to check for leaks in the inside thu the rainy season. We do this all for our friends from Id who leave their Airstream thu the summer.
rocmoc n AZ