safe/temp portable sat mount on roof ideas

You may want to consider using a drainage mat. You don't need to get anything fancy like the heavy industrial rated ones, most commercial grade units are heavy enough to hold the antenna in place. Even some of the thicker rubber type doormats will work. They are nice and heavy to prevent slipping but flexible enough to mold to curvatures. The holes let you use ties or straps to hold things to it and they drain water. I would think its a better option over wood. And when not needed for the antenna, it can be used like a mat outside the RV.