By late on Friday, Ida was packing sustained winds of up to 80 miles per hour (129 kph), according to the National Weather Service, which expected the storm to intensify significantly before coming ashore as a major hurricane in southeastern Louisiana on Sunday afternoon or evening.
According to the the US National Hurricane Center (NHC), Ida is now entering the Gulf of Mexico, adding that it is expected to rapidly intensify before reaching the northern Gulf Coast.
Forecasters said Ida would likely make US landfall as a robust Category 4 storm on the five-step Saffir-Simpson scale, generating steady winds nearing 140 mph, heavy downpours and a tidal surge expected to plunge much of the Louisiana shoreline under several feet of water.
Inundation from Ida’s storm surge – high surf driven by the hurricane’s winds – will likely reach between 10 and 15 feet around the mouth of the Mississippi River, with lower levels extending east along the adjacent coastlines of Mississippi and Alabama, according to the National Hurricane Center.
Scattered tornadoes, widespread power outages and inland flooding from torrential rain across the region were also expected.
Louisiana Governor John Bel Edwards, his state already reeling from a public health crisis stemming from a fourth wave of the COVID-19 pandemic, urged residents to ready themselves for the hurricane immediately.
“Now is the time to finish your preparations,” he told a Friday afternoon news conference. “By nightfall tomorrow night, you need to be where you intend to ride out the storm.”
“Ida certainly has the potential to be very bad,” said Brian McNoldy, a hurricane researcher at the University of Miami. “It will be moving quickly, so the trek across the Gulf from Cuba to Louisiana will only take 1.5 days.”
People were getting ready in New Orleans on Friday, lining up for groceries and petrol and filling sandbags at places around the city.
Soon after being upgraded from tropical storm to hurricane status, Ida smashed into Cuba’s small Isle of Youth, off the southwestern end of the Caribbean island nation, toppling trees and tearing roofs from dwellings.
The streets of Havana, the capital, were empty as residents shuttered themselves at home ahead of Ida’s arrival, which government forecasters warned could bring storm surges to Cuba’s western coastline.
Jamaica was also flooded by heavy rains, and there were landslides after the passage of the storm. Many roads were impassable, forcing some residents to abandon their homes.
Ida, the ninth named storm and fourth hurricane of the 2021 Atlantic hurricane season, may well exceed the strength of Hurricane Laura, the last Category 4 storm to strike Louisiana, by the time it makes landfall, forecasters said. But it pales in comparison to Katrina, the monster Category 5 storm that devastated the region in August 2005, claiming more than 1,800 lives.
A hurricane watch was in effect from Cameron, Louisiana to the Mississippi-Alabama border — including Lake Pontchartrain, Lake Maurepas and metropolitan New Orleans.
A dangerous storm surge was also possible along the Gulf Coast. If it pushes a storm surge at high tide, Ida could overlap some levees, with 2.1 to 3.4m (7 to 11 feet) of water predicted from Morgan City, Louisiana, to Ocean Springs, Mississippi.
“There is an increasing risk of life-threatening storm surge, damaging hurricane-force winds, and heavy rainfall Sunday and Monday, especially along the coast of Louisiana,” the hurricane centre said.
The mayor of Grand Isle, a Louisiana town on a narrow barrier island in the Gulf, said a voluntary evacuation late Thursday would become mandatory on Friday.
By the time it reaches the central Gulf Coast Sunday, Ida could dump 15 to 30cm (6 to 12 inches) of rain, with 50cm (20 inches) in isolated areas, from southeast Louisiana to coastal Mississippi and Alabama through Monday morning. More heavy rains are likely across Mississippi when Ida moves inland, causing “considerable flash, urban, small stream, and riverine flooding”, the hurricane centre said.