Post-Landfall Summary | Summary
Posting Date: August 30, 2021, 12:00:00 PM
Category 4 Hurricane Ida made its first landfall near Port Fourchon, Louisiana, about 60 miles south of New Orleans, at 11:55 a.m. CDT with a maximum sustained wind speed of 150 mph, and the storm made its second landfall at 2 p.m. CDT southwest of Galliano, Louisiana on Sunday, August 29, with a maximum sustained wind speed of 145 mph. The storm also produced heavy rains and dangerous storm surges.
Around the second landfall, a NOAA National Ocean Service tide gauge in Shell Beach, Louisiana, reported a water level of 6.8 feet above mean higher high water, which is an approximation of inundation in that area and a NOAA National Ocean Service tide gauge at Bay Waveland Yacht Club, Mississippi, reported a water level of 5.6 feet above mean higher high water, which is an approximation of inundation in that area.
Preliminary Reported Damage and Disruption
Only one death so far has been reported as resulting from Ida. The Ascension Parish Sheriff’s Office reported that someone had died after a tree had fallen on them. Those killed by Hurricane Katrina, which struck exactly 16 years earlier, numbered to about 18,000. The levees in New Orleans held during this storm, although levees failed in Jefferson Parish near Lafitte and Jean Lafitte and in Plaquemines Parish near Rte. 23 in Alliance.
The Governor of Louisiana said there were roughly 1,500 people in 23 shelters; these numbers are expected to increase as people discover that their homes are no longer habitable. Evening curfews are in place in various parishes.
More than 1 million customers lost power in Louisiana on Sunday and 850,000 remain without power today, including all of New Orleans; Jefferson, St. Bernard, and Plaquemines parishes; and parts of St. Charles and Terrebonne parishes. More than 130,000 remain without power in Mississippi. The Sewerage and Water Board of New Orleans advised people not to run dishwashers or washing machines to minimize wastewater because sewage pump stations had been knocked out by power outages.
Entergy provides power to the area and has said that it will begin assessing the damage today. It may take days just to make the assessment of how long it will take to restore power to customers. Eight Entergy transmission lines failed during the storm, including a large one near Avondale that fell into the Mississippi River; why they failed and how to fix them has yet to be determined. Entergy’s CEO said that a fairly large geographic area was impacted and that reconnecting individual customers would involve 20,000 workers from not only Entergy but also other utilities.
According to the Bureau of Safety and Environmental Enforcement, Gulf offshore producers had shut about 96% of their oil production and 94% of gas output as of Sunday. Oil companies in the Gulf of Mexico account for about 17% of U.S. oil production and 5% of natural gas output.
In preparation for the storm, oil refiners in the region had also reduced refining capacity. For example, according to reports on Sunday, the operator of the largest U.S. fuel conduit, Colonial Pipeline Co., shut two key lines that move fuel from Houston to Greensboro, N.C.; two others that run from North Carolina to Linden, N.J., were still operating.
Port Fourchon, where Hurricane Ida made its first landfall yesterday, is located at the southern tip of Lafourche Parish and is a docking site for ships that supply and support about 90% of the Gulf of Mexico’s platforms and rigs. About 1,200 trucks use La. 1 to access the port each day; that highway's southern reaches, outside Lafourche's hurricane protection levee, was underwater all day Sunday.
On Saturday, in anticipation of the storm, officials mandated evacuation for the port. The full extent of the damage has yet to be assessed, as crews have not yet been able to be deployed to survey the damage; however, the port’s executive director Chett Chiasson surmised that the damage would be “substantial.” According to a study cited by Chiasson, each day the port is closed, there is a USD 46 million loss to the oil and gas industry and a USD 500 million loss toward the national gross domestic product.
NHC Forecast Track and Intensity
As of 10 a.m. CDT today, Ida had weakened to a tropical storm with a maximum sustained wind speed of 40 mph and a minimum central pressure of 996 mb, according to the National Hurricane Center (NHC). It was located at 31.9°N 90.7°W, with its center farther inland over western Mississippi and moving north at 9 mph. Its strongest winds are along the coasts of Mississippi and Alabama. As the storm moves farther inland, additional weakening is expected; Ida is anticipated to weaken to a tropical depression this afternoon. The storm should continue to weaken as it moves over the Tennessee Valley tomorrow and is forecast to become extratropical on Wednesday as it moves over the eastern United States.
NHC Forecast Hazards
Dangerous storm surge inundation will continue into this afternoon along portions of the coasts of Mississippi and Alabama. Tropical storm–force winds, especially in gusts, will continue over parts of southeastern Louisiana, southern Mississippi and southern Alabama this afternoon. Ida will continue to produce heavy rainfall tonight through Tuesday morning across parts of southeast Louisiana, Mississippi, and western Alabama, resulting in considerable flash and urban flooding and significant river flooding impacts. Rivers in the Lower Mississippi Valley will remain elevated into next week. As Ida moves inland, additional considerable flooding impacts are likely across areas of the Tennessee Valley, the Ohio Valley, and particularly in the central and southern Appalachians into the Mid-Atlantic through Wednesday.
AIR recommends that ALERT™ subscribers continue to use the similar stochastic event (SSE) IDs provided yesterday to understand impacts from Hurricane Ida to their portfolios.
AIR will provide an update on plans for further deliverables for Ida tomorrow.