the cloud tops) and merge again at ( beneath the clouds). Rainfalls of diamonds have been suggested to occur, as well as on Saturn and the ice giants Uranus and Neptune. The temperature and pressure inside Jupiter increase steadily inward as the heat of planetary formation can only escape by convection. At a surface depth where the atmospheric pressure level is , the temperature is around . The region where supercritical hydrogen changes gradually from a molecular fluid to a metallic fluid spans pressure ranges of with temperatures of , respectively. The temperature of Jupiter's diluted core is estimated to be with a pressure of around . Atmosphere The atmosphere of Jupiter extends to a depth of below the cloud layers. Cloud layers Jupiter is perpetually covered with clouds of ammonia crystals, which may contain ammonium hydrosulfide as well. The clouds are located in the tropopause layer of the atmosphere, forming bands at different latitudes, known as tropical regions. These are subdivided into lighter-hued zones and darker belts. The interactions of these conflicting circulation patterns cause storms and turbulence. Wind speeds of are common in zonal jet streams. The zones have been observed to vary in width, colour and intensity from year to year, but they have remained stable enough for scientists to name them. The cloud layer is about deep, and consists of at least two decks of ammonia clouds: a thin clearer region on top with a thick lower deck. There may be a thin layer of water clouds underlying the ammonia clouds, as suggested by flashes of lightning detected in the atmosphere of Jupiter. These electrical discharges can be up to a thousand times as powerful as lightning on Earth. The water clouds are assumed to generate thunderstorms in the same way as terrestrial thunderstorms, driven by the heat rising from the interior. The Juno mission revealed the presence of "shallow lightning" which originates from ammonia-water clouds relatively high in the atmosphere. These discharges carry "mushballs" of water-ammonia slushes covered in ice, which fall deep into the atmosphere. Upper-atmospheric lightning has been observed in Jupiter's upper atmosphere, bright flashes of light that last around 1.4 milliseconds. These are known as "elves" or "sprites" and appear blue or pink due to the hydrogen. The orange and brown colours in the clouds of Jupiter are caused by upwelling compounds that change colour when they are exposed to ultraviolet light