What is the weather like on Jupiter?

The so-called gas giants - Jupiter, Saturn, Neptune and Uranus - have atmospheres composed mainly of hydrogen and helium. Jupiter's atmosphere probably extends into its core (about 43,000 miles (69,000 kilometers) deep)—although at a depth of about 600 miles (1,000 kilometers), hydrogen compresses into a liquid state. The gas becomes denser and more metallic as it goes deeper. On a clear night, Jupiter's typhoon known as the Great Red Spot can be seen covering an area three times the size of Earth. On the solar system's windy planets: Saturn and Neptune, rotating typhoons are just as violent—1,200 miles per hour (1,900 kilometers per hour). Uranus, tilted completely sideways, has 20-year-long seasons: when widespread frigid storms erupt with temperatures reaching -300°F (-184°C), signaling the start of the spring melt.