I've spent most of the evening piecing together various television, Internet, and print media reports together trying to determine the extent of the damage to New Orleans. Most reports have come in near downtown, for obvious reasons, but there have been scattered reports elsewhere. Note that there have been few reports thus far from the Mississippi and Alabama coastlines -- everything I've heard has bordered on total destruction -- so I am just going to focus on New Orleans for now.
Of all areas in and around Southeast Louisiana, the central business district appeared to fare the best. Areas around the Superdome & downtown have sustained some major wind damage, with several building collapses and numerous trees down, but they largely escaped flooding and storm surge impacts. The French Quarter is in much the same boat as the CBD.
As you move more than about 10 blocks away in any direction, however, things get worse in a hurry. Reports of 12-15ft of water have come in near Tulane University. Slightly lower amounts have been found SW of town and between town and the Tulane area, but this still leaves 4-8' of standing water. Similar wind damage has occurred in this area to those downtown.
The worst part of town, as the media reports have focused on, is the West Bank and the 9th Ward, all largely between the Mississippi and the Gulf waters themselves. This includes areas such as Chalmette and is a microchasm of what was likely seen further to the SE in areas such as Venice and Buras. Most of this area took a direct hit from the western eyewall and has seen waters to the tops of houses. Making things worse is the fact that this area had the greatest percentage of people who could not or would not evacuate. I imagine many buildings in this area are total losses.
The Slidell area appears to have suffered from a similar fate, even with quite a bit of flooding, but the impacts from flooding are not quite as great there due to the angle of the coastline.
As you head north out of New Orleans, towards the lake, water levels rise once again. Parts of I-10 are still above water, but many parts of it are not. Areas around the Metairie Cemetary are under 12-15' of water. Heading west towards Metairie and Kenner -- and the New Orleans/Louis Armstrong Intl. Airport & Jefferson Parrish -- waters overtopped the levee system and have resulted in 4-6' of water in many locations. Some areas may have been spared floodwaters in homes and businesses, but only just so; slight undulations in elevation are the likely culprits for this. Nevertheless, roads such as Metairie Ave., Airline Hwy., and Williams Blvd. have sections under many feet of water. Water began topping the levees along the lake in Kenner and Metairie early Monday and continued into the afternoon hours.
Note that many people trying to get into the city from the west are stuck in the middle on elevated portions of road due to the higher waters between the east side of Metairie and the north/west sides of downtown.
Regions west of the airport in St. Charles Parrish, such as Destrehan, suffered an even worse fate due to the lack of levee protection. The levees end right along the St. Charles/Jefferson Parrish border, not far from the airport, and part of this distinction led to parts of both parrishes flooding. The flooding does not appear to be quite as bad here as to the east of the city, but still worse than most other parts of the city. Wind damage does not appear to be quite as bad, but the water is bad enough to cause major structural damage.
Residents say this event is worse than the extreme flooding of the city that occurred during May 8-9, 1995, where over 12" of rain fell at the airport in a 24hr span. Flooding was widespread across town and resulted in over $3 billion in damages, the costliest non-tropical weather event in US history. Coupled with the higher flood waters and the very strong winds, a conservative estimate of damage in New Orleans alone is likely $6 billion dollars. This does not even account for damage done to oil rigs in the Gulf, anything occurring south and southeast of the city near where the storm made landfall, or anything in Mississippi and Alabama (yet alone Florida, Georgia, and shortly Tennessee). The LSU damage estimate predictions -- available at http://www.nola.com/hurricane/content/katrina_projected_flooding082805.pdf -- appear to match very well with what was observed in the city, not a surprise given that these particular projections were run for a 115mph category 3 storm passing over the city -- essentially what the city saw on the west side of a slightly stronger Katrina.
Many, many people -- 775,000 last I saw -- have lost power and the entire region except for the CBD is under a boil water alert. The standing waters are going to be full of disease over the coming weeks and months and it is going to take probably a full month for the waters to recede in the eastern parts of the city. The safest parts of the city probably will not open back up for residents until late this week, if that, and power will likely not be restored for some time to come. While New Orleans was spared the absolute worst and the images coming in out of the CBD, bad as they are, may suggest that the city wasn't affected all that badly, everywhere else in and around town took the full force of this storm and took it hard. Keep everyone in your thoughts and prayers over the weeks to come as they try to recover from this storm.
If I get a chance and reports start to file in from the MS/AL coastlines -- a few are available at http://www.sunherald.com/mld/sunherald/12508173.htm -- I'll try to work on a similar report for those regions. Do note that in a 2.5hr span from 6-8:30p ET in the Atlanta region, 32 separate tornado warnings were issued for cells along the eastern periphery of the storm. The effects of this system are still far-reaching, even as it spins down, and will have to be watched through the middle of the week as it heads towards the NE US.
A very good source to keep up-to-date with the latest reports from New Orleans is the Nola.com blog at http://www.nola.com/newslogs/breakingtp/...08.html#074957. It is updated on a near-constant basis with the latest information. In the half-hour I spent gathering this information, a pumping station in Kenner came back online -- good news for the west side -- and a report from Mandeville came in, suggesting they largely escaped flooding but most roads are impassable due to downed trees.
Current Tropical Model Output Plots
(or view them on the main page for any active Atlantic storms!)