Ida is the fifth-costliest tropical cyclone on record, and the fourth-costliest Atlantic hurricane in the United States, having caused at least $75.25 billion (2021 USD) in damages. The flooding in New York City prompted the shutdown of much of the transportation system. Several intense tornadoes and catastrophic flash flooding swept through the entire region, which had already been impacted by several tropical cyclones, Elsa, Fred, and Henri during July and August. The remnants of the storm produced unexpectedly severe damage in the Northeastern United States on September 1–2. Numerous tornadoes were spawned by Ida as it moved over the Eastern United States. There was also substantial plant destruction in the state.
New Orleans' levees survived (unlike during Katrina), though power line damage was extensive throughout the whole city. Widespread heavy infrastructural damage occurred throughout the southeastern portion of the state, as well as extremely heavy flooding in coastal areas. Throughout its path of destruction in Louisiana, more than a million people in total had no electrical power. Ida knocked down palm trees and destroyed many homes in Cuba during its brief passage over the country. The precursor to Ida caused catastrophic and deadly flash flooding in Venezuela. Lawrence and stalled there for a couple of days, before being absorbed into another developing low-pressure area early on September 5. Afterward, Ida's remnant moved into the Gulf of St. On September 1, Ida transitioned into a post-tropical cyclone as it accelerated through the Northeastern United States, breaking multiple rainfall records in various locations before moving out into the Atlantic on the next day. Ida weakened steadily over land, becoming a tropical depression on August 30, as it turned northeastward.
On August 29, the 16th anniversary of Hurricane Katrina making landfall, Ida made landfall near Port Fourchon, Louisiana, devastating the town of Grand Isle.
A day later, the hurricane underwent rapid intensification over the Gulf of Mexico, and reached its peak intensity as a strong Category 4 hurricane while approaching the northern Gulf Coast, with maximum sustained winds of 150 mph (240 km/h) and a minimum central pressure of 929 millibars (27.4 inHg). Amid favorable conditions, Ida intensified into a hurricane on August 27, just before moving over western Cuba. On August 26, the wave developed into a tropical depression, which organized further and became Tropical Storm Ida later that day, near Grand Cayman. The ninth named storm, fourth hurricane, and second major hurricane of the 2021 Atlantic hurricane season, Ida originated from a tropical wave in the Caribbean Sea on August 23. The remnants of the storm also caused a tornado outbreak and catastrophic flooding across the Northeastern United States. In terms of maximum sustained winds at landfall (150 mph (240 km/h)), Ida tied 2020's Hurricane Laura and the 1856 Last Island hurricane as the strongest on record to hit the state. state of Louisiana on record, behind Hurricane Katrina in 2005. Hurricane Ida was a deadly and destructive Category 4 Atlantic hurricane that became the second-most damaging and intense hurricane to make landfall in the U.S.