NOAA-NASA GOES Project(NEW ORLEANS) -- Hurricane Isaac pounded the Gulf Coast Wednesday, overtopping a levee southeast of New Orleans, knocking down trees and cutting power to more than 400,000 homes. There were no reports of injuries but dozens of residents of Plaquemines Parish, La., were stranded atop a levee, while there were multiple reports of people trapped in attics by rising waters. Thus far, fewer people were evacuated than during Hurricane Katrina, which hit New Orleans seven years ago today. But the Category 1 slow-moving storm is expected to stay over the region all day with its drenching rains and high winds. As of 9 a.m. the storm's center was about 40 miles southwest of New Orleans, according to the National Hurricane Center. At 9 a.m., 30 to 40 vehicles were stranded atop the levee in Plaquemines waiting for a ferry, with water all around, according to a contractor who works for the parish. That ferry is the only way off that flooded spit of land. A source told ABC News that nearly the entirety of the area has been flooded, and winds still howling at 35-40 mph, prevented a ferry from approaching. It is estimated that it will be six to eight hours before it's safe for the ferry to motor out to the stranded people, who were without power but do have cell phone service. Thousands who live in the area are still stuck in their homes or attics, and rescuers are out in boats helping those who need it most. "I've got a four-by-four hole in my roof, several pieces in the front yard, the back wall of my house moved a couple of feet, and with each gust of wind, it's like you're breathing in and out," William Harold "Billy" Nungesser, president of Plaquemines Parish, told Good Morning America.Nungesser confirmed that a levee in Plaquemines Parish was overtopped with water, causing flooding. So far there were no reports that the $14 billion of levees and pumps put up around New Orleans after Katrina have been breached, but officials have not yet fully assessed the situation. "The water came up so quickly and overtopped the levees from Breakaway to White Ditch on the east back of the north end of the parish. It's an area that we called for a mandatory evacuation," he said. At daylight, parish officials were out examining the damage, according to James Madere, a parish geographic information system analyst. The Plaquemines Parish Public Information Office tells ABC News that rescue operations will not start until it is safe, possibly as late as 1 p.m. ET. In New Orleans, power lines were down, snaking and sparking across city streets after transformers exploded across the city Tuesday night. The city saw handfuls of arrests early as looters took advantage of the chaos, sheriffs and police and National Guard were all out in force. The hurricane promised to lend even more solemnity to commemoration ceremonies Wednesday for Katrina's 1,800 dead in Louisiana and Mississippi, including the tolling of the bells at St. Louis Cathedral overlooking New Orleans' Jackson Square. This storm is far less powerful at Category 1 than Katrina, which caused at least $81 billion in damage and was rated as the most powerful Category 5 storm. As of 9 a.m., Isaac was still packing winds of 80 mph. Isaac is moving at near 6 mph and has already dropped more than six inches of rain on New Orleans. Hurricane force winds extend 60 miles from the center of the storm. The hurricane had moved back into the Gulf of Mexico after making its initial landfall Tuesday evening. Isaac's center remained over water where it was almost stationary before making landfall again this morning. The 200-mile wide hurricane is expected to gradually weaken and move inland in a northwestward motion, dumping seven to 14 inches of rain across Louisiana, with some places receiving up to 20 inches, according to forecasters. The greatest concern is an expected storm surge of between six and 12 feet off the Louisiana and Mississippi coasts, four to eight feet along the Alabama coast and three to six feet on the Florida Panhandle, according to the Hurricane Center located in Miami. A storm surge of 11 feet was reported at Shell Beach, La., late Tuesday while a surge of 6.7 feet was reported in Waveland, Miss., according to the Hurricane Center. The highest wind gust was recorded at 113 miles an hour overnight in Belle Chasse, Plaquemines Parish, La. Thursday night into Saturday, Isaac will move into the Mississippi Valley and eventually into Illinois and Indiana with possibly six inches of rain for the drought-stricken Midwest. Isolated tornadoes are possible along the central Gulf Coast region and part of the lower Mississippi River Valley through Wednesday, according to the National Oceanic and Atmospheric Administration. Entergy New Orleans has listed more than 400,000 homes and businesses without power as of 5:30 a.m., according to their website. The Red Cross reported 18,000 people in 70 shelters across five states Wednesday morning. video platformvideo managementvideo solutionsvideo player Copyright 2012 ABC News Radio

Governments, business and residents have been affected. Many worked through the early part of the week to prepare to ride out the storm. The storm…

They are often the ones without a voice, left behind in a natural disaster. But 70 animals from Louisiana are now in Houston, in hopes of…

With Hurricane Isaac making it’s way to New Orleans, La., — threatening to hit the city within hours of the anniversary of Hurricane Katrina —…

National

NEW YORK — Several airlines are canceling all of their New Orleans flights in anticipation of hurricane winds and rain from Isaac. American Airlines, Southwest and United are…

Tropical Storm Isaac Shutting Down Off-Shore Oil Production Rigs Tropical Storm Isaac is shutting down off-shore oil production rigs, meaning on-shore gas prices could be…

As Houston is expected to be on the western periphery of Tropical Strom Isaac, there is rain that will be apart of the forecast for…

Despite a sun filled sky after light rain late Saturday, Republican Party officials decided to cancel Monday’s proceedings. As a result, a quarter of the…

National

NHC Atlantic Outlook ZCZC MIATWOAT ALL TTAA00 KNHC DDHHMM TROPICAL WEATHER OUTLOOK NWS NATIONAL HURRICANE CENTER MIAMI FL 200 PM EDT THU AUG 23 2012 FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO... THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL STORM ISAAC...LOCATED ABOUT 165 MILES SOUTH OF SAN JUAN PUERTO RICO...AND RECENTLY UPGRADED TROPICAL STORM JOYCE...LOCATED ABOUT 1305 MILES EAST OF THE LEEWARD ISLANDS. 1. SHOWER AND THUNDERSTORM ACTIVITY REMAINS MINIMAL IN ASSOCIATION WITH A TROPICAL WAVE LOCATED BETWEEN THE WEST COAST OF AFRICA AND THE CAPE VERDE ISLANDS. ANY DEVELOPMENT OF THIS DISTURBANCE IS EXPECTED TO BE SLOW TO OCCUR...AND THIS SYSTEM HAS A LOW CHANCE... 10 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES GENERALLY WESTWARD AT ABOUT 15 MPH. ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE NEXT 48 HOURS. $$ FORECASTER BROWN NNNN

National

NHC Atlantic Outlook ZCZC MIATWOAT ALL TTAA00 KNHC DDHHMM TROPICAL WEATHER OUTLOOK NWS NATIONAL HURRICANE CENTER MIAMI FL 200 PM EDT WED AUG 22 2012 FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO... THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL STORM ISAAC...LOCATED ABOUT 95 MILES EAST-SOUTHEAST OF GUADELOUPE IN THE LESSER ANTILLES...AND TROPICAL DEPRESSION TEN...LOCATED ABOUT 860 MILES WEST-SOUTHWEST OF THE CAPE VERDE ISLANDS. ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE NEXT 48 HOURS. && PUBLIC ADVISORIES ON TROPICAL DEPRESSION TEN ARE ISSUED UNDER WMO HEADER WTNT35 KNHC AND UNDER AWIPS HEADER MIATCPAT5. FORECAST/ADVISORIES ON TROPICAL DEPRESSION TEN ARE ISSUED UNDER WMO HEADER WTNT25 KNHC AND UNDER AWIPS HEADER MIATCMAT5. $$ FORECASTER KIMBERLAIN/ZELINSKY NNNN