Hurricane Ida was a very dangerous and damaging tropical cyclone that became the second most harmful and powerful hurricane to hit Louisiana, United States, after Hurricane Katrina in 2005. At the time it made landfall, Ida had maximum sustained winds of 150 mph (240 km/h), which tied it with Hurricane Laura in 2020 and the 1856 Last Island hurricane as the strongest storm ever recorded to hit Louisiana. The leftover parts of Ida caused a tornado outbreak and severe flooding in the northeastern United States. Ida was the ninth named storm, fourth hurricane, and second major hurricane of the 2021 Atlantic hurricane season. It formed from a tropical wave in the Caribbean Sea on August 23. On August 26, the wave became a tropical depression, which later developed into Tropical Storm Ida near Grand Cayman. On August 27, Ida became a hurricane before moving over western Cuba. The next day, Ida quickly strengthened over the Gulf of Mexico and reached its strongest point as a Category 4 hurricane with winds of 150 mph (240 km/h) and a central pressure of 929 millibars (27.4 inHg) as it approached the northern Gulf Coast. On August 29, Ida made landfall near Port Fourchon, Louisiana, causing severe damage to the town of Grand Isle. Ida weakened over land and became a tropical depression on August 30 as it moved northeast. On September 1, Ida changed into a post-tropical cyclone as it moved quickly through the northeastern United States, breaking rainfall records in several areas before heading into the Atlantic the next day. Later, Ida’s leftover parts moved into the Gulf of St. Lawrence, where they stayed for a few days before being absorbed into another weather system on September 5.
Before Ida reached Louisiana, it caused deadly flash flooding in Venezuela. In Cuba, Ida knocked down palm trees and damaged many homes. In Louisiana, more than a million people lost power. Heavy damage occurred in the southeastern part of the state, and coastal areas experienced extreme flooding. New Orleans’ levees remained intact, unlike during Hurricane Katrina, but power line damage was widespread. There was also significant damage to crops and plants in the state. Ida produced many tornadoes as it moved over the eastern United States. The leftover parts of Ida caused severe damage in the northeastern United States on September 1–2, including intense tornadoes and flash flooding. This region had already been affected by earlier storms, including Elsa, Fred, and Henri. Flooding in New York City led to the shutdown of much of the transportation system.
Ida is the sixth most expensive tropical cyclone on record and the fifth most expensive Atlantic hurricane in the United States. It caused at least $75.25 billion in damages (2021 USD). Of this, $18 billion was in Louisiana, $250 million in Cuba, and $584 million was from agricultural damage in the United States, exceeding the damage caused by Hurricane Ike in 2008. CoreLogic estimated that Ida caused $16 to $24 billion in flooding damage in the northeastern United States, making it the most expensive storm to hit the region since Hurricane Sandy in 2012, with an estimated $44 billion in insured losses.
A total of 112 people died because of Ida, including 92 in the United States and 20 in Venezuela. In the United States, 32 deaths occurred in New Jersey, 30 in Louisiana, 18 in New York, 5 in Pennsylvania, 2 in Mississippi, 2 in Alabama, 2 in Maryland, 1 in Connecticut, and 1 in Virginia. Many people in the greater New Orleans area were hospitalized or died from carbon monoxide poisoning after using portable gas generators in homes with poor ventilation. For example, three members of a family of four in Marrero, Louisiana, died on September 1, 2021.
Meteorological history
A weak tropical wave moved away from the coast of Africa and entered the Atlantic Ocean on August 14. The wave moved slowly westward through a region of rising air without showing signs of organization for several days. On August 21, the wave reached an area with steady winds to the west of 45°W, where a large area of thunderstorms stretched from east to west. As the wave passed over the Windward Islands, the thunderstorms grew more widespread, and the National Hurricane Center (NHC) began tracking the system as it moved westward into the Caribbean Sea. The next day, the wave interacted with a large area of low pressure over the north coast of South America, creating a much larger low-pressure system with pressure readings near or below 1006 mbar (29.71 inHg) over the southwestern Caribbean Sea by late that day. On August 25, a strong center of rotation formed on the eastern side of the low-pressure system, and thunderstorms became more organized around it. The NHC then determined that the system had a high chance of developing as it turned north-northwestward. The system became more organized the next day south of Jamaica. At 12:00 UTC on August 26, the system was strong enough to be classified as Tropical Depression Nine, about 115 miles (185 kilometers) south-southwest of Negril, Jamaica. The depression moved north-northwestward before turning northwestward, guided by a high-pressure area over the western Atlantic Ocean. Warm waters in the northwestern Caribbean Sea, low wind shear, and a moist environment helped the system strengthen further.
Late on August 26, at 18:00 UTC, a Hurricane Hunters flight found that the depression had strengthened into Tropical Storm Ida, 130 miles (210 kilometers) southeast of Grand Cayman, Cayman Islands. At first, Ida had an uneven shape, with its strongest winds and thunderstorms to the east of its center. This was caused by wind shear, which gradually weakened. As Ida moved through the Cayman Islands and toward northwestern Cuba, its structure improved, with better outflow and rainbands. Thunderstorms also formed a dense cloud cover around the center. Ida then rapidly strengthened, with wind speeds increasing by 35 mph (55 km/h) in just over 11 hours. Late on August 27, at 18:00 UTC, the NHC upgraded Ida to a Category 1 hurricane, based on data from the Hurricane Hunters. Around the same time, Ida made its first landfall on Cuba’s Isle of Youth with winds of 80 mph (130 km/h) and a central pressure of 987 mbar (29.15 inHg). After crossing Cuba, Ida made its second landfall at Playa Dayaniguas in Pinar del Río, Cuba, with the same wind speeds and a slightly higher central pressure of 988 mbar (29.18 inHg). The system continued northwestward, and its center emerged over the southeastern Gulf of Mexico between 01:00–02:00 UTC on August 28. Although Ida did not lose strength, its movement over Cuba and the mixing of dry air into its southwestern side limited further intensification, and its strength remained nearly unchanged for several hours after reaching the Gulf.
On August 28, microwave satellite images and Cuban radar data showed Ida’s central core reorganizing with a ring of thunderstorms forming around its center. Combined with light wind shear and warm sea surface temperatures, this led to a second, more significant period of rapid intensification starting around 12:00 UTC on August 28. Ida became a Category 2 hurricane by 00:00 UTC on August 29 and a Category 4 hurricane six hours later as it moved northwestward toward the Louisiana coast. At 12:00 UTC that day, Ida reached its peak intensity, with 1-minute sustained wind speeds of 150 mph (240 km/h) and a central pressure of 929 mbar (27.43 inHg), located southwest of the mouth of the Mississippi River. During this phase, wind speeds increased by 70 mph (110 km/h), and the central pressure dropped by 57 mbar (1.683 inHg). At its peak, Ida had a nearly symmetrical structure with a well-defined eye and a visible stadium effect. Strengthening slowed as the storm began an eyewall replacement cycle, forming a second, larger eyewall around the first one. Ida remained near its peak strength. At 16:55 UTC, Ida made its third and final landfall near Port Fourchon, Louisiana, with winds of 150 mph (240 km/h) and a central pressure of 931 mbar (27.49 inHg). This tied the 1856 Last Island hurricane and Hurricane Laura as the strongest landfalling hurricane in Louisiana based on wind speed, and it ranked second only to Hurricane Katrina based on central pressure at landfall. A ship near the landfall point confirmed this intensity, with reported gusts as high as 172 mph (277 km/h).
After landfall, Ida weakened slowly at first, remaining a dangerous major hurricane. Mesovortices, or small whirlwinds, were visible within the eye. Ida kept Category 4 winds for four hours after landfall and Category 3 winds for the next four hours due to the "brown ocean effect," where the heat from Louisiana’s marshes and flat land helped Ida retain its strength longer. As the storm moved inland, most of its clouds shifted northeast of the center, and Ida began to weaken rapidly. It dropped below hurricane strength early on August 30 and weakened to a depression later that day. The NHC issued its final advisory on Ida, handing over responsibility to the Weather Prediction Center (WPC). The system became an extratropical low two days later as it moved over the central Appalachian Mountains. As Ida moved through the northeastern United States on September 1–2, it merged with a frontal zone, causing record rainfall and regaining tropical-storm-force winds before moving into the Atlantic. On September 3, Ida’s remnants moved northeastward across Atlantic Canada, bringing heavy rain and strong winds to the region. Ida’s remnants reached the Gulf of St. Lawrence, where it slowly moved in a counterclockwise loop while maintaining wind speeds of 45–50 mph (75–85 km/h). The low-pressure system became a trough late the next day as a new mid-latitude low formed to the east.
Preparations
On August 26, 2021, the Cayman Islands received a Tropical Storm Warning. Because Hurricane Grace had struck the area just one week earlier, many people were worried about another storm. Schools and businesses closed, and the government activated emergency teams, including the Cayman Islands Regiment and Coast Guard, to help with rescue and recovery efforts. People rushed to stores to buy supplies. Cayman Airways canceled some flights and moved others to later dates. The utility company said there would likely be little or no power outages.
On August 28, 800 people, including teachers and students studying turtles on the Guanahacabibes Peninsula, were evacuated because of Hurricane Ida, according to local officials. La Palma sheltered 6,281 people from the storm.
On August 29, tornado watches were issued for parts of Louisiana, Alabama, and Mississippi. The Storm Prediction Center said there was a 5% chance of tornadoes in those areas. Storm surges were expected to be 16 feet high in Louisiana, 6–9 feet in Mississippi, 3–5 feet in Alabama, and 1–3 feet in Florida. A high risk of flash flooding was issued for New Orleans and nearby areas. Heavy rainfall of 15–20 inches was predicted when Ida made landfall. About 95% of U.S. oil production in the Gulf of Mexico was shut down. By September 17, insured damages from Ida in the United States were estimated at $31–$44 billion, with $25–$35 billion in the Gulf region and $6–$9 billion in the Northeast.
On August 27, a preseason NFL football game between the Arizona Cardinals and New Orleans Saints, originally scheduled for the next day at Caesars Superdome, was canceled because of the storm’s expected strength. The game had already been moved to noon from 7 PM earlier that day. Governor John Bel Edwards declared a state of emergency. On August 28, New Orleans Mayor LaToya Cantrell ordered a mandatory evacuation for areas outside the city’s flood protection system. That same day, President Joe Biden signed an emergency declaration for Louisiana.
In a briefing on August 28, one day before Ida made landfall, Governor Edwards said the storm could be one of the strongest to hit Louisiana since the 1850s. He also said Ida would be the most severe test of New Orleans’ levee system since the 2005 failures during Hurricane Katrina. Hospitals were already near full capacity due to the ongoing COVID-19 surge, and officials worried that Ida victims would fill hospitals in affected areas.
In Mississippi, at least 15 school districts and universities closed on August 30, along with 12 casinos. Entergy Mississippi warned of major damage to its power system in the Jackson area.
On August 30, heavy rain was still expected in southeastern Louisiana, coastal Mississippi, and southwestern Alabama. Similar warnings were issued for Tennessee, Ohio, and the Mid-Atlantic region as the storm moved north. Tens of millions of people were at risk of heavy rain, flooding, and tornadoes on September 1. More than 14.5 million people were under an enhanced risk of severe weather, including a 10% chance of tornadoes. Extreme rainfall was expected in New York City, with Central Park possibly receiving more rain in one day than the city usually gets in an entire month. Flash flood watches were issued for all five New York City boroughs, Long Island, and several counties in New Jersey. On August 31, Pennsylvania Governor Tom Wolf declared a disaster emergency in anticipation of flooding, severe storms, and tornadoes from Ida’s remnants.
Impact
Hurricane Ida caused flooding in western Venezuela on August 23, which resulted in 20 deaths. In Cuba, strong hurricane-force winds knocked down many palm trees on Isla de la Juventud. On August 27, La Fe recorded wind speeds of 50 mph (80 km/h) with gusts reaching 71 mph (114 km/h). In La Coloma, Pinar del Río, and other areas, many homes were damaged, and trees lost branches. Power outages occurred in Los Palacios and Consolación del Sur. Hospital workers in Cuba continued their duties during the storm. Ida caused $40 million in insurance losses and $100 million in total damage in Cuba.
In Louisiana, Hurricane Ida caused extreme damage, with many homes destroyed or damaged. Storm surges and heavy rain led to widespread flooding. Power outages affected much of the southeastern part of the state. As Ida moved into the Northeastern United States, its remnants created several tornadoes, some of which were strong and damaging. Heavy rain and flash flooding occurred in many areas of the Northeast. Ida caused at least $65 billion in damage in the United States, with many deaths reported in Louisiana, New Jersey, and New York.
Coastal areas of Louisiana, including New Orleans, Golden Meadow, Houma, Galliano, LaPlace, Lockport, and Grand Isle, suffered severe damage. In Houma, strong winds and debris caused widespread destruction, and power services were temporarily lost. A flood warning was issued in Braithwaite after a levee overflowed. In Galliano, many homes were destroyed, trees were uprooted, and power lines were knocked down. The Lady of the Sea General Hospital in Galliano lost part of its roof.
In New Orleans, the French Quarter experienced significant damage, including collapsed buildings and destroyed roofs. The historic Karnofsky Shop collapsed. A 400-foot power tower near the Avondale Shipyard fell, damaging transmission lines in the Mississippi River. Power was restored to some areas within 10 days, but others remained without electricity for longer. Investigations were launched into the tower collapse.
At least 10 deaths in New Orleans were linked to heat caused by power outages, including photographer Laura Bergerol and residents in senior housing. About one million people in Louisiana lost power. Two drowning deaths were reported, including a man in New Orleans who drove through floodwater.
A ferry on the Lower Algiers-Chalmette route broke free during the storm and ran aground. Part of the Gulf Outlet Dam was overtopped by storm surge. The Mississippi River near Belle Chase flowed backward due to the surge. The St. Stephen Catholic School in New Orleans lost its roof.
After the storm, oil production along the Gulf Coast was shut down. Thousands of emergency workers were deployed in Louisiana, and hundreds of residents were rescued. Power outages in heavily affected areas were expected to last up to a month. States of emergency were declared in Louisiana and parts of the Northeast. Some sporting events were moved, delayed, or canceled.
An anemometer in Grand Isle recorded a wind gust of 148 mph (238 km/h) before being destroyed. In Prairieville, a man was killed when a tree fell on his home. An anemometer in Port Fourchon recorded a wind gust of 172 mph (277 km/h) when Ida made landfall.
Major damage occurred in Jefferson Parish. On August 30, insured damage was estimated at $15 billion. In lower Jefferson Parish, eight feet of water overtopped levees, forcing residents in Lafitte to flee to rooftops. The Waterford Nuclear Generating Station was shut down due to a loss of power, but emergency generators kept it safe. Two weak tornadoes, EF1 and EF0, damaged homes and trees near Slidell. A man in Slidell was presumed dead after being attacked by an alligator in floodwater. The alligator was captured and killed on September 13. Human remains were found in its stomach.
Aerial photos showed widespread destruction, debris, and flooding. On August 31, a 24-year-old man was found dead in New Orleans, likely from carbon monoxide poisoning. On September 1, 12 people, including seven children, were hospitalized for the same cause. Three more deaths from carbon monoxide poisoning were reported in Jefferson Parish. Nearby, nine people were hospitalized in St. Tammany Parish for the same reason.
Storm surge flooded much of Southeastern Louisiana, with over 6 feet of water in many areas. Plaquemines Parish experienced a storm surge of at least 14 feet. Grand Isle, near the landfall point, was hit by 10.2 feet of surge, leaving the island uninhabitable. Up to 12 breaks in its sand levee caused 100% of structures to be damaged, with 40% completely destroyed. The police station’s roof was torn apart. A man in St. James Parish was killed when a shed fell on him during the storm. Four deaths were reported in Tangipahoa Parish among nursing home residents. Power outages led to one death in New Orleans from heat exhaustion and another in St. Tammany Parish from lack of oxygen. Another person died after falling from a roof during repairs. Agricultural damage was estimated at up to $584 million.
On September 7, four people died and 141 were hospitalized in Louisiana from carbon monoxide poisoning after using generators indoors during power outages. The Louisiana Department of Health recommended placing generators at least 20 feet away from homes and using carbon monoxide detectors.
A week after the storm, over a million people in southeast Louisiana still lacked power. By the end of September 2021, about 90% of the state’s power had been restored, except in areas with severe damage.
Aftermath
The storm closed nearly all oil production along the Gulf Coast, which made up about 15% of the U.S. total. Refineries on Louisiana’s mainland were also closed, which accounted for 12.5% of the nation’s refining capacity. The Colonial Pipeline was partially closed because of the hurricane. These events caused oil and gasoline prices to rise across the United States. Early estimates of losses covered by insurance ranged from $15 billion to $25 billion. Losses in the Gulf Region’s offshore and onshore areas were estimated at up to $35 billion.
Recovering from the power outage in New Orleans was expected to take weeks, but most power was restored within 10 days after repairing a transmission line from Slidell and restarting the New Orleans Power Station. The Massachusetts Task Force sent an 80-person team to Baton Rouge on August 29 to help with the effects of Hurricane Ida. The team included emergency medical technicians, doctors, specialists in communication and logistics, and others. People in low-income areas had difficulty leaving because they could not afford to. States like Texas and South Carolina and national non-profits collected donations to help victims and support rescue efforts.
Over 5,000 National Guard members were sent to help with recovery, and more than 25,000 workers across the country supported these efforts. President Joe Biden declared a major disaster in the state, which allowed for additional funding and recovery support. Hot weather after the storm made life harder for people without power or food. More than 2 million people were under heat warnings after the storm passed. Officials said some people might not have power restored for up to a month, which could be dangerous because of the extreme heat.
The Louisiana National Guard activated 4,900 personnel and sent about 200 high-water vehicles, 70 rescue boats, and 30 helicopters. By August 30, crews rescued 191 people and 27 pets after checking 400 homes. Governor John Bel Edwards said the damage was "catastrophic" and warned the death toll might increase. Tulane University planned to evacuate all remaining students and move them to Houston. Many people went to stores and gas stations to get food, water, and fuel. Governor Edwards said the state’s levees worked as intended and kept water out.
On August 30, the college football game between Tulane and Oklahoma, originally scheduled for September 4, was moved to Norman, Oklahoma, though Tulane would still be the home team. On September 3, Tulane’s game against Morgan State, planned for September 11, was moved to Legion Field in Birmingham, Alabama. Tulane’s volleyball tournament, scheduled for September 17–18, was also moved to Birmingham. Fans could attend these events for free. On August 31, the New Orleans Saints announced they would use an interim facility in Dallas-Fort Worth for the first four weeks of the 2021 NFL season. The next day, their season opener against the Green Bay Packers was moved to TIAA Bank Field in Jacksonville, Florida.
After being closed for nearly two years, Grand Isle State Park reopened on June 1, 2023.
Emergency declarations were made in New York, including New York City, and in New Jersey by governors Kathy Hochul and Phil Murphy. Some New Jersey school districts delayed or canceled classes due to flooding or weather damage. Newark Liberty International Airport had flooded terminals, and all flights were canceled. Operations resumed the next day, but delays and cancellations continued. On September 2, the college football game between Rutgers and Temple, originally scheduled for that day, was postponed to September 4 because of flooding at SHI Stadium. Connecticut Governor Ned Lamont declared a state of emergency for the entire state due to widespread flooding.
Rescue teams used boats to help people in flooded areas in Philadelphia, northern Delaware, and parts of New York. Thousands of rescues happened in Pennsylvania alone the day after the storm. First responders in New York helped people escape from subway trains that had stopped because of flooding. Some people were stranded overnight, and hundreds of rescues happened the next day.
Major flooding caused homes and businesses in Manville, New Jersey, to catch fire after utility damage. The fires burned for hours, and fire crews could not reach them because of high floodwaters. Manville had the worst flooding in the state. Other areas with flooding included Woodbridge Township, Carteret, Rahway, Perth Amboy, Newark, Jersey City, and Paterson.
President Joe Biden said New York received more rain on Wednesday than it usually gets in an entire month of September. New York City Mayor Bill de Blasio said Hurricane Ida was "unlike anything we’ve seen before." Most deaths in the city occurred in Queens. Rainfall in Central Park broke a 94-year record, and Newark, New Jersey, broke a 62-year record. Estimated damages in the Northeast were $16–24 billion.
Because of the extreme damage and high number of deaths caused by Hurricane Ida across the U.S., the World Meteorological Organization retired the name Ida from its list of hurricane names in April 2022. The name will never be used again for an Atlantic tropical cyclone. It was replaced with Imani, which will appear on the 2027 hurricane season list.