Francine updates: Storm pushes across South as tropical depression

Tropical storm conditions have reached the Louisiana coastline, and life-threatening storm surge and hurricane-force winds are expected to begin in the next few hours leading up to Hurricane Francine’s landfall.

A hurricane watch is in effect in New Orleans, where the worst impacts will be Wednesday afternoon through Wednesday night.

A tornado watch has been issued for parts of Mississippi and Louisiana, including New Orleans.

Storm surge will worsen throughout the day. Up to 10 feet of storm surge is possible in parts of Louisiana; up to 5 feet is possible in the New Orleans area.

Flash flooding is a major threat for Louisiana and Mississippi.

Conditions across Louisiana will start to improve overnight as Francine weakens and moves north into Mississippi.

Francine will rapidly weaken after landfall and become a tropical storm by Thursday, but it’ll still bring heavy rain to the South.

Flash flooding will remain a threat through the end of the week as Francine moves north into Tennessee, Kentucky and Missouri.

The threat for isolated tornadoes will continue through Thursday morning, especially in Alabama and the Florida Panhandle.

-ABC News’ Melissa Griffin

Conditions are deteriorating in southern Louisiana as Hurricane Francine gets closer to landfall.

The storm, located 120 miles southwest of Morgan City, Louisiana, is moving northeast at 13 mph.

Rain bands are moving on shore and the dangerous winds are closing in.

-ABC News’ Melissa Griffin

With hours to go until Hurricane Francine makes landfall in Louisiana, "the time to evacuate has now passed," Jacques Thibodeau, the director of the Governor's Office of Homeland Security and Emergency Preparedness, said at a news conference.

"It is now time to go down and hunker down," he said. "We are no longer in the, 'Prepare for a hurricane' -- we are now in the, 'Respond to a hurricane.'"

The White House has approved an emergency declaration for the state. The Louisiana National Guard expects to have 2,400 guardsmen ready for the storm, along with 58 boats, 101 high water vehicles and 61 aircrafts, officials said.

Louisiana Gov. Jeff Landry said he’s been in contact with the Federal Emergency Management Agency and the Army Corps of Engineers, and said he’s fully confident in all state and federal agencies working together before, during and after the hurricane.

Landry also encouraged residents to “take advantage of the power that you have currently and make sure that you charge all of your devices.”

-ABC News’ Alexandra Faul

Residents in New Orleans should stay off the roads beginning at noon ET and remain sheltered in place until Thursday morning, Mayor LaToya Cantrell said.

"Conditions will worsen throughout the day—stay safe!" she tweeted.