Arthur’s ghost haunts the Gulf Coast with relentless flooding

Flooding rain risk for Tuesday from NOAA's Weather Prediction Center. (CNN Weather via CNN Newsource)

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Arthur is no longer a tropical system, but its leftover moisture and energy are still fuelling a deadly flood threat across the Gulf Coast and into the South during the weeklong weather event.

A rare Level 4 of 4 high risk of flooding rainfall was issued by the Weather Prediction Center for parts of Florida, Mississippi, Alabama and Louisiana through early Friday morning. Arthur’s “ghost”— its lingering, moisture-rich air — is responsible for this dangerous threat for areas that have already been soaked throughout the week.

It’s hard to overstate just how significant these high risk flooding events are. They are issued on fewer than 4 per cent of days per year on average, but they are responsible for 80 per cent of all flood-related damage and 36 per cent of all flood-related deaths, WPC research shows.

Friday into Saturday, a Level 3 of 4 risk of flooding rainfall is in place for much of the Gulf Coast, including southeastern Louisiana, southern Alabama, southern Mississippi, part of the Florida panhandle and far southwestern Georgia.

A county road crew member was killed while working on storm cleanup in Franklin County, Mississippi, Gov. Tate Reeves said on social media.

Flooding already killed two people in Texas earlier this week before Arthur formed, and the continued high-stakes flooding risk is keeping local officials on high alert.

Flood watches for the system’s heavy rain have been issued for more than 17 million people along the northern Gulf Coast to as far east as parts of Georgia. Rainfall rates of up to 6 inches per hour are possible at times in some of these areas.

Days of rain swamp Louisiana and Mississippi

Flooding touched off by relentless downpours forced evacuations and water rescues in Louisiana and Mississippi Thursday. Both states have endured days of rain as Tropical Storm Arthur and its remnants swept across the Gulf Coast. At least four flash flood emergencies — the highest level of warning — were issued in the two states this week.

A flash flood emergency was issued for Seminary, Mississippi early Friday as catastrophic flooding inundated homes and businesses and prompted water rescues. Local law enforcement reported vehicles stranded and abandoned in floodwaters after 7 to 11 inches of rain fell, with another 1 to 3 inches possible, the National Weather Service said.

The emergency management director for Covington County where Seminary is located told CNN multiple vehicles are trapped, two roadways have been shut down and four homes have been damaged, though no injuries have been reported thus far.

About 30 homes downriver of southern Mississippi’s Anchor Lake Dam were under an evacuation order Thursday amid fears the floodwaters would cause the dam to fail and unleash a dangerous deluge. Officials ultimately decided they have “high confidence in the dam’s structural integrity,” and residents were allowed to return to their homes Thursday night. Officials are still on site monitoring the dam, the Pearl River County Office of Emergency Services said in a post on Facebook.

Nine inches of rain have fallen in the area near the dam, and the East Hobolochitto Creek a few miles south rose about 14 feet in two days. Water rescues took place in neighbouring Harrison County on the Gulf Coast, according to the Mississippi governor.

In Louisiana, Gov. Jeff Landry issued a state of emergency Thursday evening to respond to storm damage across the state. About 150 homes were flooded in Avoyelles Parish in east-central Louisiana that day. The parish’s small community of Plaucheville saw about 2 feet of rain in just 12 hours during a flash flood emergency, and a nursing home in DuPont had to be evacuated.

In addition to flooding, Arthur’s remnants produced multiple tornadoes in southeast Louisiana. An EF1 tornado struck Avondale — just south of New Orleans — early Thursday morning, destroying four homes and causing minor damage to around a dozen others, Jefferson Parish spokesperson Rachel Strassel told CNN.

One mobile home was blown off its cinder blocks and struck a neighbouring modular home, which resulted in two people being taken to the hospital, Strassel said. A woman in a third home said the storm blew her out of bed and shattered the windows. Office buildings were damaged, and a stationary train blown off its tracks elsewhere in the parish, the spokesperson said.

Tornadoes also spun up in Terrebonne and St. Tammany parishes in southern Louisiana. Homes were damaged and streets flooded in the city of Houma near the Gulf Coast, and “multiple high water evacuations out of homes” were conducted in St. Tammany northeast of New Orleans, authorities said.

Through early Saturday, the remnants of Arthur are expected to produce another 5 to 10 inches of rain from central and southern parts of Louisiana east through Mississippi and Alabama, the western Florida Panhandle and western Georgia.

Flooding kills two in Texas

Parts of eastern Texas, Louisiana and Mississippi have picked up more than a month’s worth of rain in just three days, with some accomplishing this in several hours because of such heavy rainfall rates.

Some locations from southern and eastern Texas to southern Louisiana and southern Mississippi have seen over 6 inches of flooding rain so far. The highest official totals as of Thursday morning were 11.41 inches near Village Mills, Texas, and 11.31 inches near Picayune, Mississippi, according to the Weather Prediction Center.

In Bandera County, northwest of San Antonio, a woman was killed after her vehicle was swept into a flooded creek early Monday morning. Her vehicle was found “several miles downstream” and “completely submerged,” the sheriff’s office said in a statement.

On Tuesday evening, a 15-year-old boy was found dead in Magnolia in Montgomery County, part of the greater Houston metro area, after he entered a flooded retention pond while playing with a group of teenagers near a construction roadway, the sheriff’s office said in a statement to CNN.

Homes, buildings and roads flooded in areas across the region since Sunday, leaving many drivers stranded in floodwaters in Texas, Louisiana and Mississippi.

Fire crews rescued a family, including an infant, from a home with knee-deep water, Picayune Fire Department Chief Joshua Abercrombie told CNN, noting floodwater was waist-deep on the road outside the home. An estimated 8 to 9 inches of rain fell over six hours on Tuesday in the Mississippi city.

“This just dumped a tremendous amount of rain,” Abercrombie said. “We’re not used to flooding in the areas we got it in.”

By Meteorologists Chris Dolce, Briana Waxman, Mary Gilbert, and CNN’s Kate S. Petersen