Hurricane Ida was the strongest landfalling tropical cyclone during the 2009 Atlantic hurricane season, crossing the coastline of Nicaragua with winds of . The remnants of the storm became a powerful nor'easter that caused widespread damage along coastal areas of the Mid-Atlantic States. Ida formed on November 4 in the southwestern Caribbean, and within 24 hours struck the Nicaragua coast with winds of . It weakened significantly over land, although it restrengthened in the Yucatán Channel to peak winds of . Hurricane Ida weakened and became an extratropical cyclone in the northern Gulf of Mexico, before spreading across the southeastern United States. The remnants of Ida contributed to the formation of a nor'easter known as Nor'Ida, that significantly affected the eastern coast of the United States. This extratropical cyclone formed across southeastern Georgia and moved east-northeast offshore North Carolina, before slowly dropping south and southeast over the succeeding several days. The system eventually dissipated on November 17.
Numerous watches and warnings were issued during the hurricane's existence. Areas from Panama to Maine were affected by either the storm or the nor'easter low. In Nicaragua, nearly 3,000 people evacuated coastal areas ahead of the storm. More extensive evacuations in Mexico relocated over 100,000 residents and tourists. In the United States, several parishes in Louisiana and counties in Alabama and Florida declared a state of emergency because of fear of significant damage from the storm. Officials issued voluntary evacuations and most schools and non-emergency offices in the region closed.
In Central America, Ida brought heavy rainfall to parts of Costa Rica, Nicaragua and Honduras. Several people were reported missing in Nicaragua, however post-storm reports denied these claims. Thousands of buildings collapsed or sustained damage and roughly 40,000 people were left homeless. Damages from Ida in Nicaragua amounted to at least 46 million córdoba ($2.12 million US$). Aside from heavy rainfall in Mexico and Cuba, little impact from Ida was reported in either country. In the United States, the remnants caused substantial damage, mainly in the Mid-Atlantic States. One person was killed by Ida after drowning in rough seas, while six others lost their lives in various incidents related to the nor'easter. Widespread heavy rainfall led to numerous reports of flash flooding in areas from Mississippi to Maine. Overall, the two systems caused nearly $300 million in damage throughout the country.
Meteorological history
Hurricane Ida originated from a weak tropical wave that reached the western Caribbean on November 1, 2009. By November 2, the system spawned an area of low pressure north of Panama which moved very little over the following days. The low became increasingly organized within a favorable environment that allowed deep convection to develop. By November 4, the low had become sufficiently organized for the National Hurricane Center (NHC) to classify it as Tropical Depression Eleven. At this time, the tropical depression was situated just southwest of San Andrés Island. Convective banding features became increasingly defined throughout the day, and six hours after becoming a tropical depression, the system intensified into Tropical Storm Ida.
Light wind shear allowed Ida to quickly intensify as it slowly tracked towards the Nicaraguan coastline. Late on November 4, microwave satellite imagery depicted an eye-like featured forming within the storm. The storm tracked west-northwestward in response to a weak ridge over the north-central Caribbean Sea and a weak trough over the southwestern Gulf of Mexico; these features were also responsible for Ida's slow forward motion. Early on November 5, the storm intensified into a Category 1 hurricane on the Saffir–Simpson hurricane scale as it passed near the Corn Islands. At approximately 1117 UTC, the center of Ida made landfall near Tasbapauni, Nicaragua, with winds of . After the hurricane moved inland, the high mountains of Nicaragua caused the convection associated with the hurricane to diminish, resulting in rapid weakening. Roughly 18 hours after landfall, Ida weakened to a tropical depression as it turned northward over Honduras.
Late on November 6, Ida re-emerged over water, entering the northwestern Caribbean Sea. Upon moving back over water, the storm quickly began to redevelop, with convection increasing around the center of circulation. Early on November 7, Ida restrengthened into a tropical storm as it tracked just west of due north. Very warm sea surface temperatures ahead of the system would have allowed for substantial intensification; however, wind shear over the area quickly increased, resulting in modest strengthening. Later that day, the storm turned northwestward in response to a strong trough over Mexico and a mid-level ridge extending from the Southeast United States to Hispaniola. As Ida neared the Yucatán Channel, an eye redeveloped and the storm quickly intensified into a hurricane. By the morning of November 8, the storm had attained Category 2 status with winds of .
Late on November 8, Ida attained its peak intensity with winds of and a barometric pressure of 975 mbar (hPa; ). Shortly thereafter, increasing wind shear and forward speed caused the storm to rapidly weaken to a tropical storm. Only a small area of convection remained near the center by the morning of November 9. Despite the strong shear, the storm quickly re-organized, attaining hurricane status for a third time during the afternoon. Based on readings from a nearby oil platform and reconnaissance data, it was determined that Ida attained its secondary peak intensity near the southeast coast of Louisiana with winds of . However, this intensification was short-lived as a combination of increasing wind shear and decreasing sea-surface temperatures induced weakening to a tropical storm within three hours.
By the morning of November 10, all of Ida's convection appeared displaced to the northeast and the forward motion of the storm slowed substantially. Additionally, the storm had begun to undergo an extratropical transition near the United States Gulf Coast. Shortly before making landfall near Dauphin Island, Alabama, the storm completed its extratropical transition. Ida crossed Mobile Bay shortly thereafter, and maximum winds decreased below gale-force. After slowly tracking eastward for several hours, the surface circulation of Ida dissipated over the Florida Panhandle, at 12:00 UTC on November 11.
Preparations
Central America
Shortly after being designated as Tropical Storm Ida on November 4, the government of Nicaragua issued a tropical storm warning for the entire coastline of Nicaragua, and the government of Columbia also issued a warning for the nearby islands of San Andrés and Providencia. Later that day, a hurricane watch was declared for areas between Bluefields and the Nicaragua–Honduras border. As Ida moved closer to land, the tropical storm warning for San Andrés and Providencia was discontinued. Several hours later, the tropical storm warning and hurricane watch were modified to cover areas south of the Nicaragua–Honduras border to Puerto Cabezas and a hurricane warning was issued for areas south of Puerto Cabezas to Bluefields. After Ida made landfall in Nicaragua, all hurricane advisories were discontinued and replaced by a tropical storm warning. Shortly thereafter, a tropical storm watch was declared for areas along the Honduran coastline between Limón and the Nicaragua–Honduras border. However, all watches and warnings were discontinued once Ida weakened to a tropical depression on November 6.
Throughout Nicaragua, officials evacuated roughly 3,000 people from areas prone to flash floods and landslides, as rainfall in excess of was expected to fall. About 1,100 of the evacuees were from Corn Island and Little Corn Island where their homes were not expected to hold up to hurricane-force winds. In Bluefields, roughly 1,100 people were evacuated to shelters. Authorities began stockpiling supplies such as food, blankets and water that could supply 20,000 people after the storm. Upon the formation of Ida, officials in Costa Rica placed most northern regions under a yellow alert. Personnel from the Costa Rican Red Cross were also placed on standby. In El Salvador, officials raised the disaster alert level to green, the lowest stage of alert, on November 5. As Ida neared the coastline of Nicaragua, officials in Honduras warned residents of the likelihood of heavy rainfall from the storm. In response to this, the country's disaster alert level was raised to yellow.
Northern Caribbean On November 7, Tropical Depression Ida re-entered the Caribbean Sea and restrengthened into a tropical storm, prompting the NHC to issue a tropical storm watch for areas between San Felipe, Yucatán and Punta Allen in Mexico as well as in Pinar del Río Province, Cuba. Several hours later, the watches were upgraded to warnings and a new tropical storm warning was declared for Grand Cayman. A tropical storm watch was also issued for Isla de la Juventud and a hurricane watch for areas between Tulum and Cabo Catoche, Mexico. Early on November 8, the tropical storm warning and hurricane watch for Mexico were modified to include areas from Punta Allen to Playa del Carmen and Tulum to Playa del Carmen respectively. A hurricane warning was also declared for areas between Playa del Carmen and Cabo Catoche. Later that day, the tropical storm warning for Grand Cayman was discontinued as Ida moved away from the island. Early on November 9, all watches and warnings for Cuba and Mexico were discontinued as Ida moved into the Gulf of Mexico and towards the United States.
In Mexico, officials declared a yellow alert, moderate hazard, as Hurricane Ida neared the Yucatán Peninsula on November 9. Roughly 36,000 tourists and 1,500 residents were evacuated from coastal areas of Quintana Roo. The Mexican Navy was placed on standby to assist in relief efforts once the storm had passed. Later that day, the alert was raised to red, the highest level, as hurricane-force winds and heavy rains threatened the region. A total of 95 shelters were opened in the state to house the evacuees.
United States
As Hurricane Ida moved over the Yucatán Channel on November 8, the NHC issued a hurricane watch for areas between Grand Isle, Louisiana and Mexico Beach, Florida. As the storm moved closer to the states, a tropical storm warning was declared for areas between Grand Isle and Pascagoula, Mississippi, as well as areas between Indian Pass, Florida, and the mouth of the Aucilla River. The hurricane watch was also modified to encompass a smaller area, between Grand Isle and Pascagoula. A hurricane warning was also issued from Pascagoula to Indian Pass. During the afternoon of November 9, all hurricane watches and warnings were discontinued and the tropical storm warning was modified to include areas between Grand Isle and the mouth of the Aucilla River. As Ida became extratropical, the NHC discontinued all watches and warnings on the storm on November 10.
Due to the threat of large swells, several oil rigs along the Texas coastline were evacuated as a precautionary measure. Workers from Chevron Corporation and Anadarko Petroleum were evacuated from offshore platforms while those working for ConocoPhillips and ExxonMobil remained on site. The Louisiana Offshore Oil Port was also shut down on November 9 as a result of Ida's passage. As a result of the decreased oil production, the price of oil rose more than $1 to $78 per barrel. Among the rigs that were damaged was the Transocean Marianas which was drilling the Macondo well. That vessel would be replaced on the Macondo Well by the Deepwater Horizon, which caused the Deepwater Horizon oil spill in 2010.