Here is a list of some of the most powerful hurricanes to hit the mainland U.S. based on minimum atmospheric pressure, which scientists use to rate storm intensity. A lower pressure, measured in millibars, or mb, means a more powerful storm. UNNAMED FLORIDA KEYS HURRICANE, LABOR DAY 1935 (892 MB)The hurricane struck the Florida Keys as a Category 5 storm, the highest ranking on the five-step Saffir-Simpson scale. After ravaging the Keys, the storm moved north off the western coast of Florida before turning inland. Ian almost hit as a Category 5 storm, with the wind speed falling just short of the threshold of 157 mph (252 km).

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Persons: Ian, Marco Bello, Idalia, Florida . HURRICANE CAMILLE, Camille, MICHAEL, Michael, HURRICANE KATRINA, HURRICANE ANDREW, Andrew, HURRICANE IAN, Hurricane Ian, Rich McKay, Marguerita Choy Organizations: REUTERS, National Hurricane Center, Florida Panhandle, U.S, HURRICANE, Texas Gulf, Hurricane, Thomson Locations: Fort Myers Beach , Florida, U.S, Florida, Florida , Georgia, Carolinas, FLORIDA, Florida . HURRICANE, Mississippi's Gulf, Central America, HURRICANE, New Orleans, South Miami, Dade County, TEXAS GULF, Texas, Texas Gulf Coast, Indianola, Galveston, Atlanta