Almost 800 rescued in St. John the Baptist Parish after Hurricane Ida
At least three people have died as a result of the storm.
Ida is barreling through Louisiana after making landfall in the state as a powerful Category 4 hurricane on Sunday afternoon.
It was one of the strongest hurricanes on record -- by both wind speed and pressure -- to roar ashore in Louisiana.
Ida, now a tropical storm, is hitting on the 16-year anniversary of Katrina, a Category 3 hurricane that ravaged the Gulf Coast. Hurricane Katrina unleashed a series of events, taking the lives of more than 1,800 people and leaving more than $100 billion worth of damage in its wake.
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Biden promises country's 'full might behind the rescue and recovery'
President Biden spoke about the latest updates from FEMA headquarters in Washington, D.C., and promised he was going to "put the country's full might behind the rescue and recovery."
Biden said the agency has already prepositioned resources to the states most impacted by Ida including 2.5 million meals, 3 million liters of water and generators.
He urged residents in Mississippi and Louisiana to heed the warnings by their local leaders.
"Take it seriously, really...seriously," the president said.
Nearly 320,000 customers are without power in Louisiana as Hurricane Ida moves through the state, according to poweroutage.us.
-ABC News' Will McDuffie
Residents who defied evacuation orders called to be rescued: Officials
Some of the 40 people who defied mandatory evacuation orders in Grand Isle, Louisiana, called to be rescued as Hurricane Ida made landfall, officials said.
No one was able to go rescue them, Jefferson County Parish President Cynthia Lee Sheng told reporters at a news conference Sunday afternoon.
"We're getting requests for rescue, but I do not know the status of those people, and I don't know if even [the first responders on the island] know the status of those people," she said. The number of calls emergency dispatchers received was not specified.
The 40 people who remained in the town are a mix of residents and first responders who are hunkering down during Ida.
The lone road into Grand Isle was flooded by 6 feet of water, Sheng said.
"The conditions are very, very bad right now in Grand Isle," Sheng said. "They are really getting beaten up right at this moment."
-ABC News’ Will McDuffie
Storm weakens but dangerous hurricane conditions continue
Ida remained a strong Category 4 hurricane at 3 p.m., with maximum sustained winds of 145 mph.
The center of the storm is currently 25 miles west-northwest of Grand Isle, Louisiana, after making a second landfall along the southeastern Louisiana coast, just southwest of Galliano.
The eye of the storm is continuing to come ashore, bringing powerful, damaging winds and torrential rain.
Extreme wind warnings have now been issued over an extended area, southwest of New Orleans.
A recent wind gust of 76 mph was reported at New Orleans Lakefront Airport, while wind gusts of 125 mph were reported at Golden Meadow, Louisiana. Winds are also gusting more than 115 mph in places like Houma, Thibodaux, Laplace and Gramercy.
Storm surge up of 7.2 feet is coming into Shell Beach, Louisiana, while 6.3 feet of surge was reported in Waveland, Mississippi.
Tornado watches are in effect in coastal parts of Louisiana, Mississippi, Alabama and Florida.
The heavy rain and flash flooding threats will eventually reach the Tennessee Valley Monday into Tuesday and will likely affect Waverly, Tennessee, which was recently devastated by deadly flooding.
-ABC News’ Melissa Griffin and Dan Peck
3rd storm-related death confirmed
Deano Bonano, a councilman for District 2 in Jefferson Parish, told ABC News that there has been one confirmed fatality in his parish from Hurricane Ida.
Details about the death and the identity of the victim weren't immediately available.
-ABC News' Darren Reynolds