A summary of the latest preparations and situation in each state.

(CNN) -- Much of the central Gulf Coast hunkered down as Hurricane Isaac approached Tuesday. Authorities across the region warned residents to be prepared for heavy rain, high winds, coastal storm surges and flooding.

Thousands of people in Louisiana, Mississippi and Alabama are under states of emergency. The storm conjures memories of Hurricane Katrina, which slammed the region seven years ago Wednesday and killed nearly 1,800 people.

A summary of the latest preparations and situation in each state:

Louisiana

-- Isaac, now a Category 1 hurricane, is expected to hit New Orleans late Tuesday or early Wednesday, the National Hurricane Center said.

-- More than 52,000 customers were without power as of Tuesday evening.

-- Rain from the outer bands fell on New Orleans and coastal cities on Tuesday afternoon.

-- Gov. Bobby Jindal said the storm is moving slowly, and that will mean long-lasting and powerful winds.

-- He warned of a greater chance of heavy rain, flooding and downed tree limbs and power lines.

-- Tidal surges could occur after storms have passed through areas, the governor said.

-- The new $165-million Seabrook Floodgate at the north end of the Industrial Canal was closed for the first time for a storm event.

-- Forty-one parishes have issued emergency declarations.

-- Seven parishes have announced mandatory evacuations in their jurisdictions.

-- Plaquemines Parish officials have issued a curfew from Tuesday evening to sunrise Wednesday.

-- The Department of Corrections has moved prisoners from coastal parishes to state prison facilities.

-- Flights are being halted out of the New Orleans airport Tuesday and Baton Rouge on Wednesday, authorities said.

-- Flights into Baton Rouge Metropolitan Airport on Tuesday night have been canceled.

-- Bus and street car service in New Orleans and Amtrak and Greyhound service to and from the city have been shut down.

-- President Barack Obama declared a state of emergency, and federal aid is on the way.

-- The Federal Emergency Management Agency is in charge of recovery operations, and more than 4,100 National Guard troops have been activated.

-- The Louisiana National Guard has deployed 48 boat teams and 13 communications teams.

-- New Orleans Mayor Mitch Landrieu did not issue an evacuation order but called for people outside the city's protective levees to leave.

-- The city's pump stations have backup generators ready in case of electrical outages.

-- Widespread power outages are expected, said Scott Whelchel, director of the St. Charles Parish Emergency Operations Center.

-- Crews have been evacuated from oil production platforms and drilling rigs in the Gulf of Mexico.

-- The Coast Guard has closed the Mississippi River from Baton Rouge to the Gulf of Mexico and will not respond to water emergencies until after the storm passes.

-- Cargo terminals within the Port of New Orleans have ceased operations.

-- Entergy officials said they are taking one of their nuclear power plants west of New Orleans offline.

-- The New Orleans Saints football team has moved its practices to Cincinnati.

-- Jindal is skipping the GOP convention in Tampa, Florida, because of the storm.

Florida

-- Coast Guard aircrews were searching for a missing person who had been using a personal watercraft off the coast of Pensacola.

-- More than 700 customers were without power as of Tuesday evening.

-- A tropical storm warning was in effect in parts of western Florida.

-- People were ordered to evacuate parts of downtown Pensacola and some nearby barrier islands.

-- Pensacola International Airport closed at midnight Monday.

-- Okaloosa County officials called for voluntary evacuations of low-lying areas.

-- Isaac caused minor damage as it skirted South Florida.

-- Thousands of homes and businesses remained without power in Miami-Dade County.

-- Thirty members of the Florida National Guard were activated, the governor's office said.

-- Aircraft at six military bases were relocated, the Defense Department said.

-- Because of Isaac, Republicans delayed their national convention in Tampa to Tuesday.

Mississippi

-- President Obama declared a state of emergency for southern Mississippi and ordered federal aid.

-- More than 2,500 customers were without power as of Tuesday evening.

-- Residents can call 211 for information on shelters, assistance and transportation.

-- Mandatory evacuations have been ordered in parts of Hancock and Jackson counties.

-- Gulfport-Biloxi International Airport has closed

-- A hurricane warning is in effect for the entire coast.

-- About 1,500 National Guard troops have been activated.

-- Emergency supplies are being pre-positioned at Camp Shelby, a state-owned military training post.

-- Water was rising faster than predicted. An iReporter told CNN the Tchoutacabouffa River had risen 6 feet by midafternoon and it was low tide.

-- Gulfport authorities ordered the port cleared of cargo vessels.

Alabama

-- A tropical storm warning is in effect for the entire coast.

-- Authorities are warning of strong winds, high water and storm surges.

-- Gov. Robert Bentley ordered an evacuation of parts of Baldwin and Mobile counties.

-- Residents in low-lying or flood-prone areas are urged to leave voluntarily.

-- Mobile's airport has closed for commercial flights.