Hurricane Ida Recap: Devastation in Southeast Louisiana, Then Record Flooding in the Northeast

Ida began as Tropical Depression Nine on Aug. 26 while south of the Cayman Islands. Just over six hours later, an Air Force Reserve Hurricane Hunter mission found its winds were strong enough to upgrade to Tropical Storm Ida.

A burst of thunderstorms near Ida's center then allowed it to rapidly intensify into a hurricane on Aug. 27 as it moved over western Cuba.

Ida then took advantage of very warm Gulf water, winds aloft spreading apart and plenty of moist air to rapidly intensify again from Cat. 1 to Cat. 4 status in the 24 hours ending the morning of Aug. 29.

Ida's center crossed the coast near Port Fourchon, Louisiana, at 11:55 a.m. CDT on Aug. 29. Maximum sustained winds were 150 mph, making Ida a high-end Category 4 hurricane.

Ida tied two other hurricanes for the strongest landfall on record in the state of Louisiana based on maximum wind speeds. Laura had 150-mph winds when it tracked into southwest Louisiana last year. The other hurricane to make landfall in Louisiana with winds that high was in 1856.

The hurricane weakened to a tropical storm and then a tropical depression as it tracked over Mississippi on Aug. 30.

From there, Tropical Depression Ida tracked through the Tennessee Valley to as far north as West Virginia by Sept. 1, where it was declared to be a post-tropical remnant. Ida's remnants then teamed up with a stationary front to produce major, deadly rainfall flooding in the Northeast.

Below is a breakdown of Ida's Gulf Coast storm surge, wind and rain impacts followed by a summary of the flooding its remnants caused in the Northeast.

Gulf Coast Recap

Storm Surge

Storm surge pushed water into many areas outside levee protection in southeast Louisiana, as well as along the coast in Mississippi.

Several NOAA gauges captured peak inundation from 6 to 7 feet above dry ground in Waveland, Mississippi, and Shell Beach, Louisiana, during and even after Ida's landfall as strong onshore winds continued to pile water ashore.

Serious storm surge flooding was accompanied by wind gusts over 100 mph in Grand Isle, Louisiana, and multiple homes were reportedly removed from their foundations by storm surge in Galliano, about 25 miles northwest of Grand Isle.

In Plaquemines Parish, overtopping of a levee submerged the town of Braithwaite, also flooded from Hurricane Isaac in 2012. In Jefferson Parish, flooding swamped areas south of New Orleans including Lafitte and Barataria.

Water almost up to a stop sign was seen flowing through the Venetian Isles neighborhood in New Orleans East, an area under mandatory evacuation outside of protection from levees, according to WDSU TV.

Several feet of storm surge from Lake Pontchartrain coupled with torrential rain was captured in video in LaPlace, about 25 miles west-northwest of downtown New Orleans, entering homes and trapping residents.

The combination of storm surge and torrential rain prompted the NWS to issue rare flash flood emergencies for the lakeshore area of metro New Orleans, and also for St. John the Baptist and St. Charles Parishes, including LaPlace late on Aug. 29.

Post-storm surveys will likely find higher storm surge inundation values near the coast once meteorologists examine buildings for high-water marks.

Winds

The National Weather Service issued several extreme wind warnings for parts of southeast Louisiana on Aug. 29, a rarely-issued warning for tornado-like winds of 115 mph or greater in the eyewall of Ida.

According to NOAA's Best Track database, no Category 3 or stronger hurricane had taken a northward path just west of New Orleans similar to Ida in almost 106 years.

Numerous wind gusts over 100 mph were clocked in far southeast Louisiana near the coast, including in Galliano and Dulac. A gust to 172 mph was measured aboard a ship in Port Fourchon as Ida made landfall, one of the strongest hurricane gusts on record in the U.S.

Damage was reported in many areas of southeast Louisiana, particularly in Lafourche and Terrebonne Parishes.

In the New Orleans metro area, wind gusts up to 99 mph not only downed trees and power lines, but also damaged or destroyed some older buildings. Damage was captured on video in the French Quarter, and in other parts of the city.

The winds knocked out power to all of Orleans Parish due to what Entergy referred to as "catastrophic transmission damage". Over 1 million customers lost power in Louisiana from Ida.

Downed trees littered a stretch of Interstate 10 outside of New Orleans, leaving only one lane passable for a time, according to a video posted in social media.

Rainfall Flooding

As if water surging from the Gulf of Mexico wasn't enough, Ida dumped torrential rain in parts of Louisiana, Mississippi, Alabama and the western Florida Panhandle.

Ten to 14 inches of rain was measured in New Orleans before rain ended early Aug. 29. Rigolets-Slidell, Louisiana, reported 15.73 inches of rainfall from Ida.

In Jackson County, Mississippi, an estimated 300 homes were flooded and 150 road closures were prompted. More than 10 inches of rain fell near Bay St. Louis and in Hancock. Streets were also flooded in Hattiesburg and Meridian.

Parts of southern Alabama picked up 7 to 9 inches of rain and Wilmer, Alabama, measured 11.24 inches. Walnut Hill, Florida, tallied 8.20 inches of rain.

Ida's Disastrous Northeast Flooding, Tornadoes

The remnant moisture and energy from Ida merged with a front over the mid-Atlantic and Northeast to produce disastrous flooding Sept. 1 into early Sept. 2.

Flemington, New Jersey, had the top rainfall total with 11 inches, but totals over 6 inches were reported in parts of southeast New York, Pennsylvania, Massachusetts, Connecticut and Rhode Island.

New York City's Central Park picked up 3.15 inches of rainfall in a single hour on the evening of Sept. 1. That's the heaviest one-hour rainfall on record there. Total rainfall for Sept. 1 was 7.13 inches, making it New York City's fifth-wettest day on record dating to 1869.

Newark, New Jersey, picked up 8.41 inches of rain on Sept. 1, making it the wettest calendar day on record there dating to 1931. The previous heaviest rainfall day was 6.73 inches on Nov. 8, 1977.

The Schuylkill River in Philadelphia experienced its worst flood in more than 150 years on the morning of Sept. 2. Its crest of 16.35 feet has only been exceeded one other time. That happened more than 150 years ago in an Oct. 4, 1869 flood when the river hit its all-time record stage of 17 feet.

At least 12 locations on rivers and creeks in New Jersey and Pennsylvania have set a new record flood stage. Here's a rundown of the records so far, among reporting stations with records dating to at least the 20th century:

-Millstone River at Weston, New Jersey

-Musconetong River at Bloomsbury, New Jersey

-North Branch Raritan River Near Raritan, New Jersey

-Middle Brook at Bound Brook, New Jersey

-Bound Brook at Middlesex, New Jersey

-Stony Brook at Princeton, New Jersey

-Raritan River at Manville, New Jersey

-Saddle River at Ridgewood, New Jersey

-Perkiomen Creek at Graterford, Pennsylvania

-Schuylkill River at Norristown, Pennsylvania

-East Branch Brandywine Creek Below Downington, Pennsylvania

-Brandywine Creek at Chadds Ford, Pennsylvania

Destructive tornadoes tore through Annapolis, Maryland; Mullica Hill, New Jersey; and other parts of the Delaware Valley north and south of Trenton, New Jersey.

The Mullica Hill, New Jersey, tornado was the first to be rated at least F/EF3 in the state since Oct. 18, 1990, according to NOAA's database. Doppler radar detected debris from the tornado was lofted to at least 23,000 feet, and may have traveled 30 to 45 miles downstream, according to the National Weather Service.

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