Thundercloud may refer to:
- The floor of the Arcane Labyrinth from Final Fantasy II.
- The weapon from Final Fantasy XI.
- The weapon from Final Fantasy XIV.
- The support ability from Final Fantasy XIV.
- The ability from Final Fantasy Fables: Chocobo Tales.
Cumulonimbus cloud, from the Latin cumulus ("heap") and nimbus ("rainstorm", "storm cloud"), is a dense towering vertical cloud associated with thunderstorms and atmospheric instability, forming from water vapor carried by powerful upward air currents.