Almost 800 rescued in St. John the Baptist Parish after Hurricane Ida

Ida has weakened to a Category 2 hurricane as it batters Louisiana. Six to 12 inches of rain has fallen in some parts of the state and another 4 to 6 inches is possible.

President Joe Biden has approved Louisiana Gov. John Bel Edward's request for a Presidential Major Disaster Declaration.

Ida is expected to weaken to a tropical storm Monday as it slowly moves into southwestern Mississippi with heavy rain, strong winds and flash flooding. Ida will continue to bring heavy rain through Monday across southeast Louisiana, coastal Mississippi and southwestern Alabama.

Through Wednesday, as Ida moves inland, considerable flooding is possible in parts of the lower Mississippi Valley, Tennessee Valley, upper Ohio Valley, Central Appalachians and Mid-Atlantic.

-ABC News' Melissa Griffin

Louisiana's Ochsner Health hospital system will evacuate 66 patients from two hospitals due to damaged roofs and windows, hospital officials said.

-ABC News' Matt Foster

In St. Bernard Parish, Louisiana, recovery will take months, not weeks, parish president Guy McInnis told ABC News.

Twenty-two barges in the Mississippi River broke loose from the storm. Four barges have been significantly damaged but none pose a threat to the levees, he said.

The storm surge didn't impact the levees rebuilt after Hurricane Katrina, but did damage some of the businesses in the fishing industry, he said.

-ABC News' Darren Reynolds

One death from Hurricane Ida has been confirmed in Ascension Parish, located between Baton Rouge and New Orleans. A 60-year-old man was pronounced dead Sunday night after a tree fell at a home in Prairieville, the state's Department of Health said.

The Ascension Parish Sheriff's Office is receiving "numerous" calls for trees into homes, Sheriff Bobby Webre told ABC Baton Rouge affiliate WBRZ.

-ABC News' Matt Foster