There is a planet (let's call it Bob) where an ancient and powerful race once lived. They built giant gravity lifts to help move massive amounts of water high up into the atmosphere for who knows what (maybe they liked heavy rain? sadly they didn't leave any notes). They are long gone now, but their gravity lifts are still running (well one of them is at least). It is constantly lifting a kilometer sized column of sea water up to the edge of space at which point it rains back down over a nearby land mass (the current inhabitants think the sea god is fighting the sun god but that's another story...)
Would such a system be enough to keep the island constantly shrouded in thick, dark rain clouds?
The gravity lift is in the shallows just offshore and the island is a couple hundred kilometers across (I'm guessing the rain would be more intense on the gravity lift side). The gravity lift runs constantly thanks to some unknown power source and has been pumping millions of tonnes of sea water every day for millions of years and will probably continue to so for a long, long time.