The planet with a large red spot that is essentially a massive storm is Jupiter. This feature, known as the Great Red Spot, is a giant, persistent anticyclone located in Jupiter's southern hemisphere. It has been observed for over 350 years and is large enough to fit two to three Earths within it. The storm exhibits winds that can reach up to 400 kilometers per hour (about 250 miles per hour). The Great Red Spot's size and longevity make it a significant point of interest for scientists studying atmospheric phenomena and the dynamics of gas giants.