<Tr> <Td_colspan="7"> Saffir--Simpson hurricane wind scale </Td> </Tr> <Tr> <Td> TD </Td> <Td> TS </Td> <Td> C1 </Td> <Td> C2 </Td> <Td> C3 </Td> <Td> C4 </Td> <Td> C5 </Td> </Tr> <P> A Category 5 Atlantic hurricane is one that is considered by the United States National Hurricane Center (NHC), to have had sustained wind speeds greater than 136 knots (157 mph; 252 km / h; 70 m / s) on the Saffir--Simpson scale . The NHC considers sustained wind speeds to be those that occur over a one - minute period at 10 metres (32.8 ft) above ground . These wind speeds are estimated by using a blend of data from a variety of sources, which include observations from nearby ships, reconnaissance aircraft, or automatic weather stations and pictures from various satellites . </P> <P> Between 1924 and 2017, 33 hurricanes were recorded at Category 5 strength . No Category 5 hurricanes were observed officially before 1924 . It can be presumed that earlier storms reached Category 5 strength over open waters, but the strongest winds were not measured . The anemometer, a device used for measuring wind speed, was invented in 1846 . However, during major hurricane strikes the instruments as a whole were often blown away, leaving the hurricane's peak intensity unrecorded . For example, as the Great Beaufort Hurricane of 1879 struck North Carolina, the anemometer cups were blown away when indicating 138 mph (222 km / h). </P>

Have we ever had a catergory 6 hurricane