Factbox: The Most Powerful Hurricanes in U.S. History by Reuters

Florida is bracing for the impending arrival of Hurricane Idalia, which is projected to intensify into a significant storm and make landfall early Wednesday in the Big Bend region, where the state’s panhandle meets the peninsula.

Idalia is expected to strengthen to a Category 3 hurricane, potentially bringing sustained winds of at least 111 mph (178 kph), creating hazardous coastal surges, and delivering heavy rainfall, with some areas in Florida, Georgia, and the Carolinas anticipating as much as 10 inches (25 cm) of rain, according to the National Hurricane Center.

Below is a list of some of the most powerful hurricanes to strike the mainland U.S., ranked by their minimum atmospheric pressure—an important metric for assessing storm intensity. A lower pressure reading, measured in millibars (mb), indicates a more powerful storm. Currently, Idalia’s pressure is at 990 mb.

Unnamed Florida Keys Hurricane, Labor Day 1935 (892 mb)
This hurricane hit the Florida Keys as a Category 5 storm, the highest classification on the Saffir-Simpson scale. It produced winds up to 200 mph (322 kph) and resulted in the deaths of over 200 World War I veterans who were working on road construction in the area. After devastating the Keys, the storm continued northward along Florida’s western coast before moving inland, ultimately claiming more than 400 lives in the state.

Hurricane Camille, 1969 (900 mb)
Camille impacted Mississippi’s Gulf Coast as a Category 5 hurricane, bringing catastrophic storm surges and winds reaching 190 mph (305 kph) that obliterated buildings and destroyed crops. Over 200 fatalities were recorded due to the storm.

Hurricane Michael, 2018 (919 mb)
In October 2018, Michael became the third most intense hurricane to make landfall in the U.S., hitting the Florida Panhandle as a Category 5 storm with sustained winds of 160 mph (257 kph). The storm was responsible for at least 74 deaths, including 59 in the U.S. and 15 in Central America.

Hurricane Katrina, 2005 (920 mb)
Katrina made landfall as a Category 3 storm, directly impacting New Orleans and causing catastrophic failures in levees and flood walls. Most of the city was inundated, and many residents had to escape to rooftops to await rescue. The storm claimed around 1,800 lives and caused approximately $108 billion in damages, making it the most expensive hurricane in U.S. history.

Hurricane Andrew, 1992 (922 mb)
Striking South Miami-Dade County in Florida, Andrew resulted in an estimated $26 billion in damages, holding the record for the most costly storm until surpassed by Katrina. The hurricane directly killed more than a dozen individuals, with additional casualties related to indirect causes.

Unnamed Hurricane, Texas Gulf Coast, 1886 (925 mb)
This hurricane devastated the Texas Gulf Coast town of Indianola, which was then competing with Galveston to become the state’s primary port. Several dozen lives were lost during the storm, which also alleviated a severe drought in the area.

Hurricane Ian, September 2022 (947 mb)
While not among the most powerful hurricanes based on minimum pressure, Ian made landfall in Florida as a Category 4 storm with winds of 150 mph (241 kph), ranking it among the strongest storms to impact the U.S. mainland in terms of wind speed. The storm narrowly missed achieving Category 5 status, as its wind speed fell just short of the 157 mph (252 km) threshold. Ian was linked to approximately 150 fatalities.