If you shoot with feathers, the moisture will ruin your arrow flight! I was practicing a few years ago in a reallight mist, and after about 10 minutes my shots were all over the place. I examined my feather fletches and noticed that they were matted down. I bought a bottle of powder to treat them against the moisture, but shortly after put a fall-away rest on and switched to plastic vanes, so I don't really know how well the powder works.