Hurricane Ida was a destructive tropical cyclone in August and September 2021, one of the most intense hurricanes to ever strike the U.S. state of Louisiana. The storm’s path spanned thousands of miles, causing catastrophic wind and storm surge along the Gulf Coast before delivering massive rainfall hundreds of miles inland. Ida’s significance lies in its dual impact: a powerful Category 4 landfall followed by devastating, record-breaking flooding across the densely populated Northeastern United States. The U.S. landfall on August 29, 2021, coincided with the 16th anniversary of Hurricane Katrina’s arrival.
Formation and Initial Trajectory
Ida’s journey began with a tropical wave that emerged from the coast of Africa in mid-August. This wave tracked westward and organized into a tropical depression on August 26, 2021, forming in the southwestern Caribbean Sea. The system strengthened rapidly, becoming Tropical Storm Ida later that same day near Grand Cayman.
The developing storm was steered north-northwestward by the flow on the southwestern side of a subtropical ridge. It quickly intensified into a Category 1 hurricane on August 27, just before making landfall over Cuba’s Isle of Youth and then the mainland province of Pinar del Río. After crossing Cuba, Ida emerged over the warm waters of the southeastern Gulf of Mexico, where conditions were highly favorable for rapid strengthening.
The hurricane underwent rapid intensification as it moved across the Gulf’s unusually warm surface waters. In a 24-hour period, Ida transformed from a Category 1 to a Category 4 storm. This quick intensification occurred as it approached the northern Gulf Coast, setting the stage for its powerful arrival on the U.S. mainland.
Landfall and Coastal Impact
Hurricane Ida made its U.S. landfall on Sunday, August 29, 2021, near Port Fourchon, Louisiana, a small community in Lower Lafourche Parish. At this point, Ida was a high-end Category 4 hurricane, possessing maximum sustained winds of 150 mph.
This wind speed tied Ida with Hurricane Laura (2020) and the Last Island Hurricane (1856) as the strongest on record to strike the state of Louisiana. The storm’s minimum central pressure at landfall was recorded at 930-931 millibars. The destruction was immediate and catastrophic in the coastal areas, particularly in Lower Terrebonne and Lafourche Parishes, including towns like Grand Isle, Galliano, and Houma.
The storm surge caused widespread flooding along the low-lying coast. In New Orleans, the storm surge briefly caused the Mississippi River to flow in reverse, and the city experienced major wind impacts. However, the city’s levee system, rebuilt and improved after Katrina, successfully prevented widespread inundation from the surge. Extensive power outages affected over a million homes and businesses across Louisiana and Mississippi as the powerful winds destroyed transmission lines and infrastructure.
Inland Path and Northeastern Effects
After landfall, Ida slowly weakened as it tracked inland, taking a northeastward path. It remained a hurricane for a time, crossing into southwest Mississippi near McComb before degrading to a tropical storm and then a tropical depression north of Jackson, Mississippi. The storm’s remnants continued to track through the Tennessee Valley, moving across northwestern Alabama and eastern Tennessee.
The moisture-rich system then accelerated and transitioned into a post-tropical cyclone on September 1 as it moved into the Mid-Atlantic region. The storm’s trajectory took it across West Virginia, central Maryland, and southeastern Pennsylvania before the center tracked across Long Island, New York. This inland path, covering over a thousand miles from the Gulf Coast, delivered its most widespread and deadly impact through excessive rainfall.
The remnants of Ida interacted with other atmospheric energy, leading to historic flash flooding across the Northeast. Widespread rainfall totals of 6 to 8 inches, with some areas receiving up to 10 inches, fell rapidly across states like Pennsylvania, New Jersey, and New York. Newark Airport in New Jersey set an all-time daily rainfall record with 8.41 inches. The record-breaking rainfall overwhelmed urban drainage systems, flooding basements, subways, and major roadways across metropolitan areas, including New York City.