Hurricane Carla ranks as the most intense U.S. tropical cyclone landfall on the Hurricane Severity Index. The third named storm of the 1961 Atlantic hurricane season, Carla developed from an area of squally weather in the southwestern Caribbean Sea on September 3. Initially a tropical depression, it strengthened slowly while heading northwestward, and by September 5, the system was upgraded to Tropical Storm Carla. About 24 hours later, Carla was upgraded to a hurricane. Shortly thereafter, the storm curved northward while approaching the Yucatán Channel. Late on September 7, Carla entered the Gulf of Mexico while passing just northeast of the Yucatán Peninsula. By early on the following day, the storm became a major hurricane after reaching Category 3 intensity. Resuming its northwestward course, Carla continued intensification and on September 11, became what would today be classified as a Category 4 hurricane. Later that day, Carla weakened slightly but was still a large and intense hurricane when the storm made landfall near Port O'Connor, Texas. It weakened quickly inland and was reduced to a tropical storm on September 12. Heading generally northward, Carla transitioned into an extratropical cyclone on September 13, while centered over southern Oklahoma. Rapidly moving northeastward, Carla's remnants reached the Labrador Sea, Canada and dissipated on September 17, 1961.

While crossing the Yucatán Channel, the outer bands of Carla brought gusty winds and severe local flooding in western Cuba and the Yucatán Peninsula, though no damage or fatalities were reported. Although initially considered a significant threat to Florida, the storm brought only light winds and small amounts of precipitation, reaching no more than 3.15 in (80 mm). In Texas, wind gusts as high as 170 mph (280 km/h) were observed in Port Lavaca. Additionally, several tornadoes spawned in the state caused notable impacts, with the most destructive twister, an F4 near Galveston, Texas, resulting in 200 buildings severely damaged, of which at least 60 were destroyed, and 8 deaths and 200 injuries. The aforementioned tornado is one of only two violent tornadoes ever recorded in a hurricane, with wind speeds in the tornado nearly 50% greater than Carla's peak intensity. Throughout the state, Carla destroyed 1,915 homes, 568 farm buildings, and 415 other buildings. Additionally, 50,723 homes, 5,620 farm buildings, and 10,487 other buildings suffered damage. There were 34 fatalities and at least $300 million (1961 USD) in losses in Texas alone. Several tornadoes also touched down in Louisiana, causing the destruction of 140 homes and 11 farms and other buildings, and major damage to 231 additional homes and 11 farm and other buildings. Minor to moderate damage was also reported to 748 homes and 75 farms and other buildings. Six deaths and $25 million in losses in Louisiana were attributed to Carla. Heavy rainfall occurred in several other states, especially in Kansas, where flash flooding severely damaged crops and drowned 5 people. Overall, Carla resulted in $325.74 million in losses and 43 fatalities.