• New Orleans mayor imposes dusk-to-dawn curfew
• More than 817,000 without power across 5 states
• Isaac's maximum sustained winds slip to 60 mph
• Emergency crews rescue people stranded by floods

Refresh this page for the latest updates or read the full CNN story here.

[Updated 10:28 p.m. ET]

[Updated 10:20 p.m. ET] Water that overtopped levees was trapped in Plaquemines Parish with nowhere to drain. Officials were considering intentionally breaching a levee downstream to allow some of the floodwater to flow back out of the inundated area, Gov. Bobby Jindal said.

Parish President Billy Nungesser said parish officials will go out at low tide to check the back levee - a second line of defense - at the town of Braithwaite and determine where to punch holes in it. It will be Saturday, at the earliest, before crews can cut the levee open, letting water flow out into the marsh.

[Updated 10 p.m. ET]

[Updated 9:52 a.m. ET]  New Orleans officials said there had been 12 incidents of looting. Police said arrests were made in each case, but didn't specify how many people were involved.

[Updated 9:48 p.m. ET] Lake Pontchartrain's water levels are "beginning to stabilize," St. Tammany Parish officials said, according to the New Orleans Times-Picayune. Water had spilled out from the lake and flooded low-lying areas of the parish.

Rescues continue in areas around the vast Louisiana lake, including Lewisburg, Guste Island, Lacombe and Slidell, the newspaper's website reported.

[Updated 9:29 p.m. ET] Joey Amann gathered family and friends into his home in Hancock County, Mississippi, to ride out the storm, he told CNN affiliate WALA.

"You know, we just figured we'd be safer in numbers. Since our house is eight feet off the ground, we figured we'd be safer there but the water just kept coming," Amann said.

"It was scary. I mean, I've never seen the water raise this fast on this road and I've been here all my life. It just came out of nowhere."

The group ended up being rescued by emergency personnel in boats.

Amann told the station he lost his home to Hurricane Katrina in 2005.

"Thirty-six years I've lived here, and it's just devastating," he said. "Seven years ago, we were going through the same thing. No one thought it would be this bad, but it's worse than we anticipated."

[Updated 9:18 p.m. ET] Power has been restored earlier than expected to most of Dauphin Island, Alabama, CNN affiliate WALA reported. The western end of the island in Mobile Bay remains in the dark because roads there are impassable, Alabama Power said.

[Updated 9:07 p.m. ET] Jefferson Parish Council member Chris Roberts said "tar patties," presumably from the 2010 BP oil spill, had washed up on Grand Isle, Louisiana, during the storm.

[Updated 8:59 p.m. ET]  A volunteer in the St. John the Baptist Parish sheriff's office said more than 200 residents in LaPlace, about 25 miles northwest of New Orleans, had been rescued from rising water coming from Lake Pontchartrain.

[Updated 8:05 p.m. ET] Tropical Storm Isaac's top sustained winds slipped to 60 mph in the National Hurricane Center's latest update. The storm was centered 30 miles south of Baton Rouge and 60 miles west of New Orleans, and had slowed its northwestern crawl even further to 5 mph.

[Updated 7:37 p.m. ET] The Federal Emergency Management Agency, in coordination with U.S. Northern Command, deployed four UH-60 Blackhawk helicopters from Fort Campbell, Kentucky, and two SH-60 Seahawk helicopters from Norfolk Naval Air Station, Virginia, to assist in search and rescue efforts.

National Guard troops moved 112 residents from a nursing home in Plaquemines Parish to another facility.

[Updated 7:16 p.m. ET] New Orleans Mayor Mitch Landrieu assured residents the drinking water has remained safe to drink throughout the storm, and the sanitary sewer system is operating perfectly, so no one needs to restrict toilet flushing.

[Updated 7:01 p.m. ET] "It appears that the worst of this storm is moving past us now," New Orleans Mayor Mitch Landrieu told CNN affiliate WWL, but he reiterated that a curfew remains in place until 6 a.m. Thursday. He also warned those who do travel the streets that many traffic signals are down, so drivers should treat every intersection as a four-way stop.

"What we got today was terrible, but I think we did a pretty good job," he added. "... A Category 1 can be as bad as a Category 5 if it hangs around."

Landrieu advised people to be very careful during the cleanup phase, when more than half of hurricane-related deaths occur.

The mayor also reminded residents that police are employing a no-tolerance policy for looting. "They're on it like gravy on rice," he told WWL.

[Updated 6:45 p.m. ET] The first line of defense in any disaster is neighbors helping neighbors.

[Updated 6:35 p.m. ET] [tweet https://twitter.com/NOAA/status/240931197079932928%5D

[Updated 6:28 p.m. ET] A 21-foot seawall built in Bay St. Louis, Mississippi, after Hurricane Katrina is "holding up very well," Mayor Les Fillingame told CNN affiliate WWL.

"Every storm has its own personality, its own footprint. ... This, for a Category 1 storm that made landfall really not that close to us, has had such persistence," he said. "This may be the new norm."

He said perhaps 100 homes will end up being flooded by the time the storm blows over, rather than the 1,000 that might have been flooded before the seawall was built and building elevation standards improved.

[Updated 6:18 p.m. ET] A new tornado warning was issued for Harrison County, Mississippi, as a persistent rain band continues to race north from the Gulf of Mexico, CNN affiliate WWL reported.

[Updated 6:01 p.m. ET] Floodwater has overtopped a third levee in Plaquemines Parish, Louisiana, Parish President Billy Nungesser told CNN.

[Updated 5:54 p.m. ET] Biloxi, Mississippi, police are stopping vehicles on city streets and enforcing a curfew until further notice, Officer Jackie Rhodes told CNN affiliate WLOX. People who were arrested for looting during Hurricane Katrina seven years ago are still in prison, he said.

[Updated 5:46 p.m. ET] The National Hurricane Center said 17 inches of rain has fallen during Tropical Storm Isaac at Audubon Park in New Orleans.

[Updated 5:41 p.m. ET] More than 817,000 customers are without power, utilities along the Gulf Coast report.

[Updated 5:06 p.m. ET] Coffins float out of flooded graves in Plaquemines Parish, Louisiana, CNN affiliate WWL reports.

[Updated 4:52 p.m. ET] The National Hurricane Center says the storm is now centered 60 miles west of New Orleans and 35 south of Baton Rouge, still packing 70 mph winds and moving northwest at 6 mph.

[Updated 4:49 p.m. ET] Harrison County, Mississippi, is under a tornado warning until 4:15 p.m.

[Updated 4:44 p.m. ET] As many as 800 homes may have suffered significant water damage in Plaquemines Parish alone, Louisiana Gov. Bobby Jindal says.

Meanwhile, water is said to be 12 feet deep and rising in Madisonville, Louisiana, CNN affiliate WWL reports.

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[Updated 4:36 p.m. ET] Flash flood warnings are in place for all or portions of the following counties:

In Louisiana: Ascension, East Baton Rouge, Jefferson, Livingston, Orleans, St. Charles, St. John The Baptist, St. Tammany, Tangipahoa, Washington

In Mississippi: Forrest, George, Greene, Harrison, Lamar, Marion, Pearl River, Perry, Stone, Walthall

In Alabama: Mobile

[Updated 4:30 p.m. ET] The National Oceanographic and Atmospheric Administration provides tools to keep abreast of weather developments.

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[Updated 4 p.m. ET] New Orleans Mayor Mitch Landrieu has imposed a dusk-to-dawn curfew in the city until further notice.

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[Updated 3:42 p.m. ET] CNN affiliate WWL reports major flooding in LaPlace, Louisiana, and boat rescues are taking place.

[Updated 3:21 p.m. ET] Public and private schools throughout southern Louisiana will not reopen until Tuesday, CNN affiliate WGNO reports.

[Updated 3:04 p.m.] Isaac has weakened to tropical storm status, as its sustained winds have dropped to 70 mph, the National Hurricane Center said. The storm's location at 3 p.m. ET was about 50 miles west-southwest of New Orleans and 55 miles south-southeast of Baton Rouge. It was crawling northwest at 6 mph.

[Updated 2:49 p.m.] Granted, this storm is no Katrina, but it's still disastrous to many people - and animals - in its path.

[Updated 2:40 p.m.] Hurricane Isaac has knocked out power to more than 725,000 customers in five states, the affected utilities report.

[Updated 2:32 p.m. ET] President Barack Obama received a briefing from federal officials on the impact of Hurricane Isaac and held a conference call Wednesday with the governors of Louisiana, Mississippi and Alabama, and the mayor of New Orleans, the White House said.

"The president heard from the governors and mayor about the current conditions on the ground and the steps their teams are taking to respond. The president asked the governors to continue to identify any additional needs if they arise as the effects of Isaac and the response efforts continue," the White House said.

[Updated 2:25 p.m. ET Wednesday] Power could be out in some areas of Louisiana for as much as a week, Bill Mole, CEO of Entergy Louisiana, tells CNN affiliate WWL.

[Updated 2:19 p.m. ET Wednesday] Hurricane Isaac's slow, rainy march through Louisiana is expected to cause as much as $1.5 billion in insured losses, according to one disaster modeling firm, CNNMoney reports.

[Updated 2:18 p.m. ET Wednesday] Heavy squalls spawned by Hurricane Isaac continue to slap New Orleans and the Mississippi Gulf Coast, the National Weather Service said. The storm's center is 45 miles southwest of New Orleans and 55 miles south-southeast of Baton Rouge, it says.

[Updated 2:13 p.m. ET Wednesday] The National Weather Service has issued a tornado warning for Harrison County, Mississippi, including the cities of Biloxi and Gulfport.

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[Updated 2:09 p.m ET Wednesday] At least 673,039 customers are without power in Arkansas, Alabama, Louisiana, Mississippi and Texas because of Hurricane Isaac, according to the latest numbers from power providers.

[Updated 2:07 p.m. ET Wednesday] On the lighter side, we have an iReport that may spark some smiles during this tough time for the Gulf Coast.

Greg Taylor of Mandeville, Louisiana, sent his wife and two children to Alabama to escape the storm. Taylor stayed behind and when he went into his daughter Ashley's room to feed her fish, a beta named Tom Brady, Taylor found that the 8-year-old had left behind a list of instructions for her stuffed animals.

Among them: "Noises: Scoot close to your buddy" and "When I'm gone: Stay Calm. No Partys."

[tweet https://twitter.com/nolaready/status/240870531967111168%5D

[Updated 1:46 p.m. ET Wednesday] Dozens of road closures have been reported by the Louisiana State Patrol over the past 24 hours. Click here for the latest information.

[Updated 1:40 p.m. ET Wednesday] Gov. Bobby Jindal says there's an unconfirmed report of a fatality in a fire at a commercial building in Gretna, near New Orleans. News reports say heavy winds from Isaac kept firefighters from battling the blaze.

[Updates 1:34 p.m. ET Wednesday] More than 8,200 National Guard personnel are available for relief operations in Louisiana, Gov. Bobby Jindal says. As of this morning, 4,130 people are in shelters across Louisiana, the governor added.

[Updated 1:32 p.m. ET Wednesday] Entergy Corporation, which provides power in New Orleans and parts of Mississippi and Texas, has 10,000 workers and contractors from 24 states responding to power outages, said spokesperson Chanel Lagarde. The company says it has more than 550,000 customers without power.

[Updated 1:26 p.m. ET Wednesday] Authorities are using high-water vehicles to evacuate nursing home residents in flooded areas of Plaquemines Parish, Gov. Bobby Jindal says.

[Updated 1:25 p.m. ET Wednesday] Gov. Bobby Jindal says authorities are considering intentionally breaching part of an east bank levee in Plaquemines Parish to relieve pressure on the levee.

[Updated 1:23 p.m. ET Wednesday] The Mississippi Highway Patrol reports the following road closures:

- U.S. 90 between Bay St. Louis and the Biloxi Bay Bridge.
- Highway 43/603 between U.S. 90 and I-10
- Highway 604 north of U.S. 90 at Pearlington
- Highway 43/603 at Jourdan River
- U.S. 90 at Whites Bayou near Pearlington
Closures are expected to last until 5 pm Friday.

[Updated 1:02 p.m. ET Wednesday] Gulf Power Company announced that it has restored power to more than 20,000 customers in Northwest Florida, CNN affiliate WKRG reports.

Scattered outages remain, and spokesman Jeff Rogers warned that more outages are possible throughout the day.

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[Updated 12:39 p.m. ET Wednesday] The University of Louisiana-Monroe is canceling classes as of 4 p.m. today through Labor Day, school President Nick J. Bruno announced on the university's website.

[Updated 12:35 p.m. ET Wednesday] Louisiana Gov. Bobby Jindal is scheduled to hold a news conference at 12:55 p.m. ET in Baton Rouge, while New Orleans Mayor Mitch Landrieu will hold one at 1:30 p.m. ET.

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[Updated 12:27 p.m. ET Wednesday] Seventy-five people have been rescued from flooded homes and rooftops in the Louisiana town of Braithwaite in Plaquemines Parish, CNN affiliate WWL reported, citing parish President Billy Nungesser. At least 25 others were "awaiting rescue on the parish's east bank on rooftops and in attics," the station reported.

[Updated 12:24 p.m. ET Wednesday] Residents have been ordered to evacuate from new areas of Plaquemines Parish, CNN affiliate WVUE reports. Water will start rising from the Oakville flood gate to Venice. School buses will be sent through the area to pick up people, the reports says.

[Updated 12:14 p.m. ET Wednesday] Not even Isaac can stop one of Louisiana's favorite pastimes: LSU still plans to play its football game against North Texas on Saturday night in Tiger Stadium in Baton Rouge, coach Les Miles tells CNN affiliate WBRZ.

[Updated 12:08 p.m. ET Wednesday] The National Weather Service has issued a tornado warning for Hancock, Harrison and Pearl River counties in Mississippi.

[Updated 12:06 p.m. ET Wednesday] Interstate 10 between Baton Rouge and New Orleans is closed because of high water, state Police Superintendent Mike Edmonson tells CNN affiliate WDSU.

[Updated 11:59 a.m. ET Wednesday] Petty officer Ryan Tippets says all Coast Guard assets are in standby mode and “as soon as the storm passes, the Coast Guard will be out there.”

[Updated 11:43 a.m. ET Wednesday] Gas prices that are rising because of Hurricane Isaac could begin to drop as early as Monday, said the Oil Price Information Service, which reports petroleum pricing news.

[Updated 11:32 a.m. ET Wednesday] Nearly 654,000 customers are without power in Arkansas, Alabama, Louisiana, Mississippi, and Texas as a result of Hurricane Isaac, power companies reported Wednesday.

[Updated 11:28 a.m. ET Wednesday] iReporter Alekz Londos is a freelance photojournalist who traveled from Santa Cruz, California, to cover Isaac. He’s submitted video of waves crashing into the Orleans Marina on Lake Ponchartrain.

[Updated 11:22 a.m. ET Wednesday] There may be a silver lining to Isaac’s arrival in the Gulf states. Though it’s too late to benefit summer crops such as corn and soybeans, the rain from the storm could bring some much-needed hydration to parts of Louisiana, Arkansas, Oklahoma, Kansas, Tennessee and Missouri, AccuWeather reports.

If the rain moves far enough westward it could also benefit the wheat crops in the central and southern Plains. Wheat is generally planted in September, AccuWeather says.

[Updated 11:19 a.m. ET Wednesday] Residents of Plaquemines Parish made more than 150 calls to be rescued from rising flood waters since 2:30 a.m. this morning, parish Cmdr. Terry Rutherford tells CNN.

Sheriff's boats, National Guard boats and civilians are participating in the rescue operations, Rutherford said.

Rutherford says there is 5 feet to 14 feet of flood water in the east bank area of the parish.

Hurricane safety tips: What to do when the lights go out

[Updated 11:15 a.m. ET Wednesday] Louisiana State University will remain closed through Thursday because of Hurricane Isaac, according to a release posted to the schools website.

[Updated 11:10 a.m. ET Wednesday] Despite annual improvements for the last several years to the Plaquemine Parish levees, they just couldn’t stand up to Isaac’s storm surge, said parish President Billy Nungusser.

“This storm was not a Category 1. This storm delivered a punch, and we saw water come over those levees more than (during) Gustav and Ivan. And it continues to flow,” he told CNN.

In Woodlawn, an area along the Mississippi River that saw no flooding during Katrina, there is 5 feet of water. In other areas along the river’s east bank, there are reports of 12 to 14 feet of water that has stranded people in attics and on roofs.

“This storm continues to just pump water into that area like we’ve never seen before.,” Nungusser said, adding that residents along the west bank are worried that Isaac could deliver destruction across the river before it passes through the area.

[Updated 11:06 a.m. ET Wednesday] At 11 a.m. ET, the National Hurricane Center says Isaac remains a hurricane with winds of 75 mph, gusting to 100 mph.  The center is directly over Houma, Louisiana, about 45 miles southwest of New Orleans. Tropical storm warnings for coastlines east of the Alabama-Florida border have been discontinued.  Hurricane warnings remain in effect for coastlines east of Morgan City, Louisiana, to the Mississippi-Alabama border, including the city of New Orleans and Lake Pontchartrain.

[Updated 11:03 a.m. ET Wednesday] The Lake Pontchartrain Causeway, a 24-mile-long bridge over the lake connecting the New Orleans suburb of Metairie with Mandeville on the north side of the lake, is closed because of high winds and will likely remain so through Wednesday, the Times-Picayune reports.

[Updated 10:48 a.m. ET Wednesday] At least 5,200 people spent the night in Red Cross shelters in the storm area, Jonathan Aiken, a spokesperson for the Red Cross tells CNN. The Red Cross operates 80 shelters in six states.

[Updated 10:46 a.m. ET Wednesday] iReporter Eileen Romero of New Orleans found two homes that had collapsed in the Mid-City neighborhood. You can see her photos here and here.

[Updated 10:40 a.m. ET Wednesday] Hurricane Isaac has left at least 559,332 customers without power in Louisiana, Arkansas, Mississippi and Alabama, power companies said Wednesday. The bulk of the outages are in Louisiana.

[Updated 10:38 a.m. ET Wednesday] Mobile Regional Airport authorities say the facility's runways will be open Wednesday and passengers will be kept informed of today's flight operations. Mobile is a southwestern Alabama city on the Gulf Coast, which has been slammed by Hurricane Isaac.

[Updated 10:31 a.m. ET Wednesday] All of Dauphin Island is without power – and this time it’s not totally Isaac’s fault.

According to CNN affiliate WPMI, a boater had to be rescued from his sail boat because of the nasty conditions on the water. The abandoned ship still had its sails raised, and it floated down toward the Dauphin Island Bridge, where it hit a power line that pumps electricity to the island’s 1,200 residents.

The ship then turned back into the Gulf and crews are trying to get the boat under control. Meanwhile, the causeway is closed and a curfew will go into effect later today.

[Updated 10:24 a.m. ET Wednesday] Hurricane Isaac is weakening "slightly" as it moves inland over southeastern Louisiana, the National Weather Service said. The storm has maximum sustained winds of 75 mph, and its center is about 50 miles south-southwest of New Orleans. A storm becomes a hurricane when those winds reach 74 mph.

[Updated 10:24 a.m. ET Wednesday] Tornado warnings have been issued for Washington Parish in Louisiana and Hancock and Pearl River counties in Mississippi, the National Weather Service says.

[Updated 10:22 a.m. ET Wednesday] Deputies and residents in Louisiana's Plaquemines Parish were working to reach people trapped in attics and on roofs by high water spawned by Hurricane Isaac, CNN affiliate WWL reported.

[Updated 10:15 a.m. ET Wednesday] Public schools in Jefferson Parish, Louisiana, will not reopen until Tuesday, the district says in a posting on its website.

[Updated 10:13 a.m. ET Wednesday] A tornado warning is in effect for parts of Hancock and Harrison counties in Mississippi, the National Weather Service says.

[Updated 10:07 a.m. ET Wednesday] Water was encroaching on an evacuation shelter in Raceland, in Lafourche Parish, reports Gina Swanson from CNN affiliate WDSU.

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[Updated 9:58 a.m. ET Wednesday] Tulane University in New Orleans has canceled all classes until Tuesday, the school has announced on its website.

"Students on campus are safe and still sheltering in place in residence halls," the school said.

[Updated 9:49 a.m. ET Wednesday] Hurricane Isaac is posing a significant threat for inland flooding. The National Oceanic and Atmospheric Administration such flooding "the hidden danger of tropical cyclones." Inland flooding accounts for more than 50% of hurricane-related deaths, NOAA says. Check out their web page on the dangers.

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[Updated 9:40 a.m. ET Wednesday] After Katrina, carpenter Bill Boesch rebuilt his and his wife’s house with an extra level “just in case.” As Isaac approached, he was prepared with coolers and a generator, but the storm conjured some unpleasant memories from seven years ago.

“It just brings all of that back up – you know, that whole experience and the loss,” he said.

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[Updated 9:22 a.m. ET Wednesday] In Mississippi, there are about 2,132 evacuees housed in 31 shelters across the state, CNN affiliate WCBI reports. The station said about 4,000 homes were without power as of 5:30 a.m. CT.

If you're in Mississippi and need to evacuate, the Red Cross has a list of available shelters on its website.

The Louisiana Red Cross has a list as well.

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[Updated 9:20 a.m. ET Wednesday] A couple, their 6-month-old baby and family dog were rescued from a houseboat on the Pearl River this morning, according to The Sun Herald, a newspaper that covers the Mississippi Gulf Coast. The incident occurred in Pearlington, just 100 feet from the Louisiana state line. Emergency and wildlife officials brought the family to safety after rising water trapped the family on the boat, the paper reported.

[Updated 9:17 a.m. ET Wednesday] 522,228 customers are without power in Arkansas, Alabama, Louisiana and Mississippi, according to power providers Entergy, Alabama Power, and Cleco.

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[Updated 9:15 a.m. ET Wednesday] The center of Hurricane Isaac is 40 miles southwest of New Orleans, the National Hurricane Center said in its latest advisory Wednesday. Strong squalls from the storm are battering southeastern Louisiana and heavy rains and a "dangerous storm surge" are likely to continue into the evening, the advisory said.

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[Updated 9:14 a.m. ET Wednesday] An elderly Florida may have been disoriented from heavy rain associated with then-Tropical Storm Isaac when she drove into a retention pond and drowned Monday, CNN affiliate WFTV in Orlando reports.

The body of 89-year-old Margaret Langewisch was found in her Mazda in the 18-foot-deep pond in Winter Springs on Tuesday.

"We had a torrential downpour for 10 or 15 minutes and I think that's what the problem was because she must have missed the first right and thought she was going to the clubhouse," resident Tony Palmiotti is quoted as saying.

[Updated 9:07 a.m. ET Wednesday] Alabama Power reports that about 5,600 customers are without power, mostly on Dauphin Island, in Bayou la Batre and other areas in south Mobile County. Another 1,100 are without power in the Theodore area. Alabama Power says all customers should have power restored by day's end.

[Updated 9:05 a.m. ET Wednesday] With Isaac now moving at the torpid pace of 6 mph, National Hurricane Center Director Richard Knabb tells CNN that the storm's eye has yet to pass through the region and residents in the area can expect pounding rain "all day today, into tonight, into tomorrow."

"For many people, it's not even half over," Knabb said.

[Updated 9:01 a.m. ET Wednesday] As Isaac's winds and rain continue to hamper government services in Louisiana and Mississippi, the city of Pensacola, Florida, has announced it is back to business, according to CNN affiliate WALA. City Hall, libraries, garbage service and the Pensacola International Airport were all operational as of this morning, the station reported.

[Updated 8:53 a.m. ET Wednesday] Three adults and one infant in Mississippi were rescued overnight from a houseboat as Hurricane Isaac hit the region, the state's emergency operations center said Wednesday.

[Updated 8:42 a.m. ET Wednesday] Today is the anniversary of Hurricane Katrina making landfall on the Gulf Coast seven years ago. CNN has put together a few pieces in remembrance of the natural disaster that killed hundreds and left the region reeling. There's a photo gallery as well as a video package revisiting the destruction left in Katrina's wake.

[Updated 8:36 a.m. ET Wednesday] The National Weather Service has issued a flash flood warning for several Louisiana cities, including Timberlane, Metairie, Marrero, Kenner, Harvey, Avondale, New Orleans, New Orleans East, Chalmette and Hahnville. The warnings, which affect St. Bernard, St. Charles, Orleans and Jefferson parishes, are in effect until 9:45 a.m. CT.

[Updated 8:31 a.m. ET Wednesday] Please remember, if you're on or near the Gulf and have stories, photos or videos to share, please send them to iReport. Thanks!

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[Updated 8:28 a.m. ET Wednesday] Mississippi and Louisiana residents who didn't evacuate and aren't in danger should stay put until the winds and rain pass, FEMA Administrator Craig Fugate said.

"We have resources ready to go, but until the winds come down, we're really asking people, if you're not somewhere that's dangerous, stay where you're at unless you're told to evacuate," he told CNN.

[Updated 8:06 a.m. ET Wednesday] In Destin, Florida, more than 200 miles east of New Orleans, there are reports of heavy damage, including a broken-down boardwalk near a condominium development. CNN affiliate WEAR reported that waters from the Gulf essentially swallowed the beach before flooding the streets in the resort town that styles itself as "The World's Luckiest Fishing Village." More than 11,000 people live in the city, which is located on an isthmus separated from the Florida mainland by the Choctawhatchee Bay.

Resident Kris Thurman told WEAR, "It seems like we've been in this pattern where every season if a tropical storm or a hurricane gets anywhere near the Gulf, even if it's not a direct hit, the sea rises and it washes out the beach."

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[Updated 7:48 a.m. ET] Several environmental groups have expressed concerns that Isaac could stir up some of the remnant crude from the BP oil spill more than two years ago. BP rejected the notion in a statement to Huffington Post.

SkyTruth, an environmental group specializing in remote sensing and digital mapping is encouraging residents in the area to post photos of any oil pollution they see to the SkyTruth website.

"That's the most obvious way that the oil might come back into the public eye. Erosion could expose and churn up tar balls and tar mats," SkyTruth President John Amos told HuffPo.

[Updated 7:44 a.m. ET] A tornado watch remains in effect for southeast Louisiana and southern Mississippi until 4 p.m. CT Wednesday, the National Weather Service says.

[Updated 7:41 a.m. ET] Gas prices shot up by nearly 5 cents a gallon nationwide Wednesday after Hurricane Isaac cut output from refineries along the Gulf Coast, CNNMoney reports.

But experts say the price spike is likely to be short lived, especially since the winds associated with the Category 1 storm are not believed to have caused lasting damage to the refineries in the region.

Wholesale gas prices were already falling Tuesday ahead of the storm making land, and were sharply lower Wednesday.

Click here for state-by-state gas prices.

[Updated 7:37 a.m. ET] Because Isaac is moving so slowly, it is not expected to complete the 70-mile trek from New Orleans to the capital, Baton Rouge, until late morning or early afternoon, several Louisiana news outlets are reporting.

According to CNN affiliate WFAB, forecasters are saying Isaac could take 12 hours to travel from south of the Crescent City to the capital and that the center of the storm is expected to pass through Wednesday afternoon. Tropical storm-force winds are expected for a "prolonged period," the station reported.

[Updated 7:34 a.m. ET] The National Weather Service issues a tornado warning for Gulfport, Biloxi and Long Beach in Mississippi.

[Updated 7:27 a.m. ET] The Louisiana attorney general has issued a statement reminding the state's sex offenders the evacuating because of the storm foes not relinquish them of the responsibility to notify law enforcement of their whereabouts, CNN affiliate WAFB reports.

They can either phone law enforcement or register their location on the internet at www.offenderwatchexpress.com.

"Under Louisiana law, you are required to notify law enforcement of any changes in residence, including any temporary situation that may cause an absence from your usual place of residence for more than seven days," according to the release.

[Updated 7:24 a.m. ET] "The water came up so quick it looks like we lost everything," a Plaquemines Parish resident tells CNN affiliate WWLTV. Listen as he talks to the station from his attic.

[Updated 7:10 a.m. ET] Its large size and slow motion are worsening the effects of Hurricane Isaac, making it seem a stronger storm than the Category 1 storm it is, Richard Knabb, director of National Hurricane Center, tells CNN’s Soledad O’Brien.

[Updated 7:03 a.m. ET] Three people have been rescued from flooding in Plaquemines Parish, including one woman rescued from a roof, parish President Billy Nungesser, tells CNN's Soledad O'Brien.

[Updated 6:54 a.m. ET] 438,150 customers are without power in Louisiana, Mississippi and Arkansas, according to power provider Entergy's storm information site.

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[Updated 6:47 a.m. ET] Louisiana Commissioner of Administration Paul Rainwater announced that all state government offices will be closed today, CNN affiliate WAFB in Baton Rouge reports.

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[Updated 6:42 a.m. ET] Animal shelters in New Orleans and Gulfport, Mississippi, were forced to ship several pets awaiting adoption to North Texas, according to CNN affiliate WDSU. The two shelters sent a collective 175 cats and 105 dogs to two Texas shelters.

To make room for the animals, which arrived yesterday, the Society for the Prevention of Cruelty to Animals is offering discounts on adoption fees, the station reported.

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[Updated 6:36 a.m. ET]  The National Weather Service has issued a tornado warning for Jackson County in southern Mississippi.

[Updated 6:32 a.m. ET]  CNN's Brian Todd in New Orleans reports rising waters in the streets.

[Updated 6:25 a.m. ET]  The National Weather Service has issued a tornado warning for portions of Hancock and Harrison counties in Mississippi.

A state-by-state look at the effects of Hurricane Isaac

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[Updated 5:49 a.m. ET]  Plaquemines Parish President Billy Nungesser is a personal victim of Hurricane Isaac, the New Orleans Times-Picayune reports.

Winds have ripped parts of the roof off his home and water has been pouring in, the paper reported.

[Updated 5:44 a.m. ET]  There have been reports of 10 to 12 feet of water in homes in Plaquemines Parish, parish President Billy Nungesser told CNN's “Early Start” anchor Zoriada Sambolin.

Nungesser said Isaac has pushed more water into some areas than Katrina did seven years ago. He said the Woodlawn area had no water in it from Katrina and has five feet of water in it now.

[Updated 5:34 a.m. ET]  In its 5 a.m. ET advisory, the National Hurricane Center says Isaac is still a Category 1 hurricane with maximum sustained winds of 80 mph.

[Updated 5:26 a.m. ET]  Billy Nungesser, Plaquemines Parish president, told CNN what happens when a levee is overtopped:

"As that water flows over the top, it eventually will eat out portions of that levee, which then it washes away.

"Either that or the inside of the levee will fill up.

"One or the other will happen. Either way that area’s going to be totally inundated with water."

[Updated 5:19 a.m. ET] Billy Nungesser, Plaquemines Parish president, spoke to CNN about the overtopping of a levee in the parish:

“We knew we were going to have trouble with the projected storm surge, but we were hoping this storm wasn’t going to sit out there as long as it has done, backtracked, and keep pumping this water up against the levees. And there’s only just so much that it can take."

[Updated 5:12 a.m. ET] Officials are reporting "overtopping of a levee on the east bank" from Braithwaite to White Ditch in Louisiana's Plaquemines Parish, which will "result in significant deep flooding in the area," the National Weather Service said.

[Updated 5:05 a.m. ET] The National Weather Service warned early Wednesday that heavy rainfall across metropolitan New Orleans and nearby coastal communities will likely result in flash floods.

[Updated 4:05 a.m. ET] The storm has resumed moving, slowly, toward the west-northwest at 8 mph, the National Hurricane Center says, after being stalled for part of the morning.

[Updated 3:15 a.m. ET] Hurricane Isaac is stationary near the coast of southeast Louisiana, the National Weather Service says. It's expected to resume a slow northwestern movement later today.

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[Updated 2:03 a.m. ET] "The center (of the storm) has wobbled westward and has moved back over water," the National Hurricane Center wrote in a late-night "forecast discussion." "A northwestward motion has recently resumed and a second landfall should occur later tonight near Grand Isle (Louisiana). ... Little change in strength is expected during the next 12 hours or so as the center moves across the bayous of southeastern Louisiana. Steady weakening should commence later Wednesday as the center moves farther inland."

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[Updated 1:52 a.m. ET] More than 256,000 Entergy Louisiana customers were without power at last count.

[Updated 1:44 a.m. ET] Cameron County, Texas, officials closed the Padre Island and Boca Chica beaches Tuesday evening because of dangerous tides and currents, CNN affiliate WBRZ reported. Three shelters - one in Dallas, two near the Louisiana line - were opened in Texas for storm-driven evacuees, the station reported.

[Updated 1:25 a.m. ET] As of 1 a.m. ET, Hurricane Isaac was 60 miles southeast of Houma, Louisiana, and 70 miles south of New Orleans, still maintaining 80 mph winds and dumping large amounts of rain on Louisiana, Mississippi and Alabama, the National Hurricane Center said. Dangerous storm surge conditions were observed all along the northern Gulf Coast.

"The combination of a storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters," the NHC advisory said. Surge levels could reach 6 to 12 feet in Mississippi and southeastern Louisiana; 3 to 6 feet in Alabama and south-central Louisiana; 2 to 4 feet along the Florida Panhandle and Apalachee Bay; and 1 to 3 feet along the rest of Florida's west coast, the center predicted.

A surge of 11 feet already had been recorded at Shell Beach, Louisiana, it said.

Isaac is expected to produce total rainfall amounts of 7 to 14 inches, with up to 20 inches possible in spots, leading to "possibly significant lowland flooding," the NHC said.

Isolated tornadoes are possible along the central Gulf Coast region and parts of the lower Mississippi Valley through Wednesday, it said.

People also should beware of rough surf and dangerous rip tides all along the coast for the next couple of days, the NHC warned.

[Updated 1:17 a.m. ET] The season-opening college football game Thursday between Louisiana Tech and Texas A&M has been postponed because of the hurricane, CNN affiliate KTVE reported. The game will be played in Ruston, Louisiana, on October 13, which was an open date for both teams, Louisiana Tech officials said.

[Updated 12:49 a.m. ET] According to CNN affiliate WGNO, the following locations are under flood warnings because of storm surge and/or heavy rain: St. Tammany, Tangipahoa and Washington in Louisiana; Pearl River and Hancock in Mississippi.

[Updated 12:34 a.m. ET] Rain fell with a vengeance along the Gulf Coast as Hurricane Isaac slowly skidded along the Louisiana coast like a Roomba bumping into a wall.

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