Clubs are exposed to outside weather in tubes, but on warm or hot days grips come loose. Work at driving range.
saw this at a driving range near St. Louis several years ago. Older clubs, kept outside in the elements, tubes would get water in them, shafts would start to rust (no graphite back then). Facility needed to regrip all of them (they cut off the rusted portion of the butt end).
What I learned – drilled holes in the bottom of my golf bag for those days when it rained out.