What category hurricane would Jupiter's Great Red Spot be?

I was asked to make this comment an answer. The May 3, 1999, tornado that struck Moore and other areas of Oklahoma City had winds measured as high as 318 mph. This is the highest windspeed ever recorded on Earth. read more

Category Five. The Saffir-Simpson scale ends at five, with sustained wind speeds in excess of 137 knots. The scale is designed to give an impression of how much damage the hurricane does. At over those speeds or above, it flattens anything in its way, no matter how well engineered. read more

Overall, nine cyclones were spotted over Jupiter’s north pole and six over the south pole. The wind speeds reach 220 mph in places, exceeding Category-5 hurricane strength. Each cyclone measures several thousand miles across. The new information comes from the NASA spacecraft Juno, which has been in orbit around Jupiter since 2016. read more

In May 2008 a third storm turned red. The Great Red Spot should not be confused with the Great Dark Spot, a feature observed near the northern pole of Jupiter in 2000 with the Cassini–Huygens spacecraft. Note that a feature in the atmosphere of Neptune was also called the Great Dark Spot. read more