1900 Galveston hurricane
The Great Galveston Hurricane, known regionally as the Great Storm of 1900, was the deadliest natural disaster in United States history, one of the deadliest hurricanes (or remnants) to affect Canada, and the fourth-deadliest Atlantic hurricane overall. The hurricane left between 6,000 and 12,000 fatalities in the United States; the number most cited in official reports is 8,000. Most of these deaths occurred in the vicinity of Galveston after storm surge inundated the entire island with of water. In addition to the number killed, every house in the city sustained damage, with at least 3,636 destroyed. Approximately 10,000 people in the city were left homeless, out of a total population of nearly 38,000. The disaster ended the Golden Era of Galveston, as the hurricane alarmed potential investors, who turned to Houston instead. The Gulf of Mexico shoreline of Galveston island was subsequently raised by and a seawall erected.
2005 Atlantic hurricane season
Hurricane Katrina formed in mid-August over the Bahamas. It became a tropical storm on August 24 and reached hurricane intensity before making landfall in south Florida as a minimal hurricane. A few hours later, the storm entered the Gulf of Mexico and intensified rapidly into a Category 5 hurricane while crossing the Loop Current on August 28. Katrina made landfall shortly after 06:00 CST on August 29 near the mouth of the Mississippi River as an extremely large Category 3 hurricane. Category 5-level storm surges (as the storm had weakened only in the previous several hours) caused catastrophic damage along the coastlines of Louisiana, Mississippi, and Alabama. Within hours, levees separating Lake Pontchartrain from New Orleans, Louisiana were breached by the surge, ultimately flooding about 80% of the city. Wind damage was reported well inland, impeding relief efforts. Katrina is estimated to be responsible for at least $125 billion (2005 USD) in damage, breaking Hurricane Andrew's record in 1992 and making it the costliest natural disaster in U.S. history until Harvey tied it in 2017. It was the deadliest U.S. hurricane since the 1928 Okeechobee Hurricane, killing at least 1,836 people. The 1900 Galveston Hurricane remains the deadliest natural disaster in United States history, with a death toll of approximately 6,000.