Tropical Storm Barry strengthened into a category one hurricane on Saturday as it neared the Louisiana coast, threatening millions with heavy rains and storm surge. The storm was expected to weaken after it moved inland but forecasters encouraged residents in New Orleans to be patient and stay vigilant.
More than 12 hours after city officials anticipating crippling and potentially historic flooding told residents to “shelter in place”, a few rays of sun peeked through the clouds on Saturday morning, adding a glint to the mostly dry city streets.
“We are sensing a great deal of impatience with the onset of impacts from Tropical Storm Barry,” said the New Orleans office of National Weather Service in a tweet very early on Saturday morning. “Plenty of very heavy rainfall parked off the coast to move through the area throughout the day Saturday into Sunday. Be patient and DO NOT drop your guard.”
The National Hurricane Center (NHC) later said the storm had duly become a hurricane.
Forecasters warned that the storm’s glacial pace towards the Louisiana coast would give it time to gather moisture from the Gulf of Mexico, potentially intensifying the rainfall to come.
The latest weather models suggested Barry could dump between 10in and 20in of rain over south-central and south-east Louisiana and south-west Mississippi. In a statement on Saturday morning, the Weather Forecast Center said the area should “expect some pretty impressive rainfall rates … with some values likely exceeding 3in in an hour”.
Experts also warned that because of the erratic and lopsided shape of the storm, its most intense bands of torrential rain may not occur until well after landfall, which was expected some time on Saturday in Morgan City, a fishing and oil town about 70 miles south-west of New Orleans.
Donald Trump declared a state of emergency for Louisiana, for the first Atlantic hurricane of 2019. While New Orleans authorities refrained from ordering evacuations, tourism officials reported an exodus of hotel guests on Friday. Airlines including British Airways, Delta and Spirit cancelled outbound flights from the city.
A performance scheduled for Sunday by the Rolling Stones at the Mercedes-Benz Superdome, which served as an emergency shelter during Hurricane Katrina in 2005, was postponed until Monday.
Most residents elected to stay and ride the storm out. Officials urged them to secure their homes, stock up on supplies and prepare to stay indoors. Bread and water aisles at several local supermarkets were picked clean by Friday.
The storm was widely expected to be a key test of flood defences put in place following Katrina, which inundated much of the city and killed about 1,800 people. A number of coastal areas without sufficient protection were evacuated. Nearly 50,000 people were without power, according to utility provider Entergy.
The storm’s flood potential, rather than its high winds, posed the greatest danger to low-lying New Orleans, a city virtually surrounded on all sides by rising waters. Benjamin Schott, a meteorologist, said: “Tropical Storm Barry is a dangerous and life-threatening storm.”
Authorities were keeping a particularly watchful eye on the levee system built to contain the lower Mississippi, which winds through the heart of New Orleans and is already well above flood stage from months of heavy rainfall over the midwest.
Early predictions that the river would crest at 20ft or 6 meters on Saturday, the height of the city’s lowest floodwalls, were revised down significantly to 17ft. The city called the risk of water overtopping the flood defenses “minimal”.
Barry was expected to skirt the western edge of New Orleans. But LaToya Cantrell, the city’s mayor, said 48 hours of heavy downpours could still overwhelm pumps designed to purge streets and storm drains of excess water.
“There is no system in the world that can handle that amount of rainfall in such a short period,” Cantrell said on Twitter.
New Orleans was already saturated after thunderstorms drenched the city with a foot of rain on Wednesday.
Early on Saturday authorities said water was flowing over the tops of a few levees in areas south of the city. Officials said the levees were in lower Plaquemines parish and were not the main levees protecting the Mississippi.
Louisiana’s lieutenant governor, Billy Nungesser, told WVUE-TV anyone south of Myrtle Grove should evacuate from low-lying, flood-prone land that follows the Mississippi to the Gulf of Mexico. Much of Plaquemines parish has been under an evacuation order since Thursday.
The US Coast Guard said it was rescuing more than a dozen people stranded on a remote island. Petty Officer Lexie Preston said some people were on rooftops on the Isle de Jean Charles, about 45 miles south of New Orleans. Preston said four people and a cat had been taken out on a helicopter. She said a boat was also heading to the area. She did not know the condition of those rescued.
The island is the home of the Isle de Jean Charles Band of Biloxi-Chitimacha-Choctaw Tribe and is part of the southern Louisiana bayous threatened by rising sea levels.