Clouds are simply condensed water vapor or ice crystals in the air mass they are in. They travel with the air they form in. If you have ever watched a thunderstorm develop what you are seeing is water vapor from rising warm air condensing in the colder air it is punching through. Eventually it hits an altitude where the wind consists of air that is essentially like leveling the head on a mug of root beer. The storm itself is a physical manifestation of the warm rising air (with lots of water vapor) and the air it displaces as it rises sinking through the core of the storm. Both rising and sinking air spiral in their respective journeys up and down. Add Coriolis effect from the rotation of the Earth can cause the entire cell to rotate, if this rotation becomes violent enough you have a tornado. Hurricanes are complexes of multiple storm cells. Over land friction from the interaction of the air over the land keeps these complexes from becoming too well organized. Put these same systems (a low pressure system) over open warm water and you have a potential to spawn a monster storm, a hurricane.