Live Thread - Hurricane Katrina, Part IV (Update: Now a Category 5 )

Category	Wind Speed	Barometric Pressure	Storm Surge	Damage Potential
Tropical Depression	< 39 mph < 34 kts			Minimal
Tropical Storm	39 - 73 mph 34 - 63 kts			Minimal
Hurricane 1 (Weak)	74 - 95 mph 64 - 82 kts	28.94" or more 980.02 mb or more	4.0' - 5.0' 1.2 m - 1.5 m	Minimal damage to vegetation
Hurricane 2 (Moderate)	96 - 110 mph 83 - 95 kts	28.50" - 28.93" 965.12 mb - 979.68 mb	6.0' - 8.0' 1.8 m - 2.4 m	Moderate damage to houses
Hurricane 3 (Strong)	111 - 130 mph 96 - 112 kts	27.91" - 28.49" 945.14 mb - 964.78 mb	9.0' - 12.0' 2.7 m - 3.7 m	Extensive damage to small buildings
Hurricane 4 (Very strong)	131 - 155 mph 113 - 135 kts	27.17" - 27.90" 920.08 mb - 944.80 mb	13.0' - 18.0' 3.9 m - 5.5 m	Extreme structural damage
Hurricane 5 (Devastating)	Greater than 155 mph Greater than 135 kts	Less than 27.17" Less than 920.08 mb	Greater than 18.0' Greater than 5.5m	Catastrophic building failures possible

Camille did, in the 60's

Nuts. It would have to be Camille :(

It is very likely to get stronger through the day.

The heat from the sun increases it's energy.

The left lane is for those going west through BR, the right lane is for those going north to I-55. Radio says too many people are trying to go west, through BR, they need to go north, not as much traffic on those roads.

Right, even commandeering commercial airliners, I doubt that you could manage more than 30 departures per hour, with say 333 people per departure, is only 10,000 per hour. The planes have to land and load as well.

And I'd guess that the airlines are already moving a good fraction of this flow.

Who knows??? The ppl running this state have never missed a chance to screw us, or they are so dumb they end up screwing things up worse....With a few exceptions of course but not many...

A guy calling FNC while en route evacuating said that most folks seem to be heading west, not north, and that the local gov't was trying to encourage folks to head north so as to help the traffic situation.

Have you been outside this morning?
No wind at all....dead air.

It seems as if they're trying to get out of its path. I'd just want out of NO and go north where there's not as much traffic.

Yeah, I'm pretty sure that this generation will be talking about Katrina the way the last generation talks about Camille.

God bless bless and protect the life and property of each. In Jesus' name, Amen.

Amen!

The eye is very defined. It's frightening but she is beautiful. Looking at a 1969 sat photo of Camille, it's almost deja vu.

What about that eyewall replacement thingies that goes on periodically? Is she due for one of those between now and lanfall?

I think it will turn, and dissipate.

All those cemetaries getting flooded with water will create a contaminated situation.

I would think it would be minor compared with all the fresh animal and human corpses, at least the ones the gators don't clean up.

Cemetaries? Read this:

NEW ORLEANS IS SINKING BY JIM WILSONPublished on: September 11, 2001

The surge of a Category 5 storm could put New Orleans under 18 ft. of water.

They don't bury the dead in New Orleans. The highest point in the city is only 6 ft. above sea level, which makes for watery graves. Fearful that rotting corpses caused epidemics, the city limited ground burials in 1830. Mausoleums built on soggy cemetery grounds became the final resting place for generations.

Beyond providing a macabre tourist attraction, these "cities of the dead" serve as a reminder of the Big Easy's vulnerability to flooding. The reason water rushes into graves is because New Orleans sits atop a delta made of unconsolidated material that has washed down the Mississippi River. Think of the city as a chin jutting out, waiting for a one-two punch from Mother Nature.

The first blow comes from the sky. Hurricanes plying the Gulf of Mexico push massive domes of water (storm surges) ahead of their swirling winds.

After the surges hit, the second blow strikes from below. The same swampy delta ground that necessitates above-ground burials leaves water from the storm surge with no place to go but up.

The fact that New Orleans has not already sunk is a matter of luck. If slightly different paths had been followed by Hurricanes Camille, which struck in August 1969, Andrew in August 1992 or George in September 1998, today we might need scuba gear to tour the French Quarter.

This is catastrophic..

There's a reason "calm before the storm" is a proverb.

Having lived through a couple when I was in NC, there's always a period of "dead air" before and after a hurricane. Afterwards is the worst. It's hot and humid with no breeze, and more than likely you're in it trying to clean up.

I think Andrew was a 3 when it hit near Houma.

I was working that night when it passed and a tornado touched down near here in LaPlace.

http://www.nola.com/hurricane/index.ssf?/washingaway/thebigone_1.html

THE BIG ONE
A major hurricane could decimate the region, but flooding from even a moderate storm could kill thousands. It's just a matter of time.

By Mark Schleifstein and John McQuaid
Staff writers

The line of splintered planks, trash and seaweed scattered along the slope of New Orleans' lakefront levees on Hayne Boulevard in late September 1998 marked more than just the wake of Hurricane Georges. It measured the slender margin separating the city from mass destruction.

The debris, largely the remains of about 70 camps smashed by the waves of a storm surge more than 7 feet above sea level, showed that Georges, a Category 2 storm that only grazed New Orleans, had pushed waves to within a foot of the top of the levees. A stronger storm on a slightly different course -- such as the path Georges was on just 16 hours before landfall -- could have realized emergency officials' worst-case scenario: hundreds of billions of gallons of lake water pouring over the levees into an area averaging 5 feet below sea level with no natural means of drainage.

That would turn the city and the east bank of Jefferson Parish into a lake as much as 30 feet deep, fouled with chemicals and waste from ruined septic systems, businesses and homes. Such a flood could trap hundreds of thousands of people in buildings and in vehicles. At the same time, high winds and tornadoes would tear at everything left standing. Between 25,000 and 100,000 people would die, said John Clizbe, national vice president for disaster services with the American Red Cross.

"A catastrophic hurricane represents 10 or 15 atomic bombs in terms of the energy it releases," said Joseph Suhayda, a Louisiana State University engineer who is studying ways to limit hurricane damage in the New Orleans area. "Think about it. New York lost two big buildings. Multiply that by 10 or 20 or 30 in the area impacted and the people lost, and we know what could happen."

Hundreds of thousands would be left homeless, and it would take months to dry out the area and begin to make it livable. But there wouldn't be much for residents to come home to. The local economy would be in ruins.

The scene has been played out for years in computer models and emergency-operations simulations. Officials at the local, state and national level are convinced the risk is genuine and are devising plans for alleviating the aftermath of a disaster that could leave the city uninhabitable for six months or more. The Army Corps of Engineers has begun a study to see whether the levees should be raised to counter the threat. But officials say that right now, nothing can stop "the big one."

Like coastal Bangladesh, where typhoons killed 100,000 and 300,000 villagers, respectively, in two horrific storms in 1970 and 1991, the New Orleans area lies in a low, flat coastal area. Unlike Bangladesh, New Orleans has hurricane levees that create a bowl with the bottom dipping lower than the bottom of Lake Pontchartrain. Though providing protection from weaker storms, the levees also would trap any water that gets inside -- by breach, overtopping or torrential downpour -- in a catastrophic storm.

"Filling the bowl" is the worst potential scenario for a natural disaster in the United States, emergency officials say. The Red Cross' projected death toll dwarfs estimates of 14,000 dead from a major earthquake along the New Madrid, Mo., fault, and 4,500 dead from a similar catastrophic earthquake hitting San Francisco, the next two deadliest disasters on the agency's list.

The projected death and destruction eclipse almost any other natural disaster that people paid to think about catastrophes can dream up. And the risks are significant, especially over the long term. In a given year, for example, the corps says the risk of the lakefront levees being topped is less than 1 in 300. But over the life of a 30-year mortgage, statistically that risk approaches 9 percent.

In the past year, Federal Emergency Management Agency officials have begun working with state and local agencies to devise plans on what to do if a Category 5 hurricane strikes New Orleans.

Shortly after he took office, FEMA Director Joe Allbaugh ordered aides to examine the nation's potential major catastrophes, including the New Orleans scenario.

"Catastrophic disasters are best defined in that they totally outstrip local and state resources, which is why the federal government needs to play a role," Allbaugh said. "There are a half-dozen or so contingencies around the nation that cause me great concern, and one of them is right there in your back yard."

In concert with state and local officials, FEMA is studying evacuation procedures, postdisaster rescue strategies, temporary housing and technical issues such as how to pump out water trapped inside the levees, said Michael Lowder, chief of policy and planning in FEMA's Readiness, Response and Recovery directorate. A preliminary report should be completed in the next few months.

Louisiana emergency management officials say they lobbied the agency for years to study how to respond to New Orleans' vulnerability, finally getting attention last year.

With computer modeling of hurricanes and storm surges, disaster experts have developed a detailed picture of how a storm could push Lake Pontchartrain over the levees and into the city.

"The worst case is a hurricane moving in from due south of the city," said Suhayda, who has developed a computer simulation of the flooding from such a storm. On that track, winds on the outer edges of a huge storm system would be pushing water in Breton Sound and west of the Chandeleur Islands into the St. Bernard marshes and then Lake Pontchartrain for two days before landfall.

"Water is literally pumped into Lake Pontchartrain," Suhayda said. "It will try to flow through any gaps, and that means the Inner Harbor Navigation Canal (which is connected to Breton Sound by the Mississippi River-Gulf Outlet) and the Chef Menteur and the Rigolets passes.

"So now the lake is 5 to 8 feet higher than normal, and we're talking about a lake that's only 15 or 20 feet deep, so you're adding a third to a half as much water to the lake," Suhayda said. As the eye of the hurricane moves north, next to New Orleans but just to the east, the winds over the lake switch around to come from the north.

"As the eye impacts the Mississippi coastline, the winds are now blowing south across the lake, maybe at 50, 80, 100 mph, and all that water starts to move south," he said. "It's moving like a big army advancing toward the lake's hurricane-protection system. And then the winds themselves are generating waves, 5 to 10 feet high, on top of all that water. They'll be breaking and crashing along the sea wall."

Soon waves will start breaking over the levee.

"All of a sudden you'll start seeing flowing water. It'll look like a weir, water just pouring over the top," Suhayda said. The water will flood the lakefront, filling up low-lying areas first, and continue its march south toward the river. There would be no stopping or slowing it; pumping systems would be overwhelmed and submerged in a matter of hours.

"Another scenario is that some part of the levee would fail," Suhayda said. "It's not something that's expected. But erosion occurs, and as levees broke, the break will get wider and wider. The water will flow through the city and stop only when it reaches the next higher thing. The most continuous barrier is the south levee, along the river. That's 25 feet high, so you'll see the water pile up on the river levee."

As the floodwaters invade and submerge neighborhoods, the wind will be blowing at speeds of at least 155 mph, accompanied by shorter gusts of as much as 200 mph, meteorologists say, enough to overturn cars, uproot trees and toss people around like dollhouse toys.

The wind will blow out windows and explode many homes, even those built to the existing 110-mph building-code standards. People seeking refuge from the floodwaters in high-rise buildings won't be very safe, recent research indicates, because wind speed in a hurricane gets greater with height. If the winds are 155 mph at ground level, scientists say, they may be 50 mph stronger 100 feet above street level.

Buildings also will have to withstand pummeling by debris picked up by water surging from the lakefront toward downtown, with larger pieces acting like battering rams.

Ninety percent of the structures in the city are likely to be destroyed by the combination of water and wind accompanying a Category 5 storm, said Robert Eichorn, former director of the New Orleans Office of Emergency Preparedness. The LSU Hurricane Center surveyed numerous large public buildings in Jefferson Parish in hopes of identifying those that might withstand such catastrophic winds. They found none.

Amid this maelstrom, the estimated 200,000 or more people left behind in an evacuation will be struggling to survive. Some will be housed at the Superdome, the designated shelter in New Orleans for people too sick or infirm to leave the city. Others will end up in last-minute emergency refuges that will offer minimal safety. But many will simply be on their own, in homes or looking for high ground.

Thousands will drown while trapped in homes or cars by rising water. Others will be washed away or crushed by debris. Survivors will end up trapped on roofs, in buildings or on high ground surrounded by water, with no means of escape and little food or fresh water, perhaps for several days.

"If you look at the World Trade Center collapsing, it'll be like that, but add water," Eichorn said. "There will be debris flying around, and you're going to be in the water with snakes, rodents, nutria and fish from the lake. It's not going to be nice."

Mobilized by FEMA, search and rescue teams from across the nation will converge on the city. Volunteer teams of doctors, nurses and emergency medical technicians that were pre-positioned in Monroe or Shreveport before the storm will move to the area, said Henry Delgado, regional emergency coordinator for the U.S. Public Health Service.

But just getting into the city will be a problem for rescuers. Approaches by road may be washed out.

"Whether or not the Airline Highway bridge across the Bonnet Carre Spillway survives, we don't know," said Jay Combe, a coastal hydraulic engineer with the corps. "The I-10 bridge (west of Kenner) is designed to withstand a surge from a Category 3 storm, but it may be that water gets under the spans, and we don't know if it will survive." Other bridges over waterways and canals throughout the city may also be washed away or made unsafe, he said. In a place where cars may be useless, small boats and helicopters will be used to move survivors to central pickup areas, where they can be moved out of the city. Teams of disaster mortuary volunteers, meanwhile, will start collecting bodies. Other teams will bring in temporary equipment and goods, including sanitation facilities, water, ice and generators. Food, water and medical supplies will be airdropped to some areas and delivered to others.

Stranded survivors will have a dangerous wait even after the storm passes. Emergency officials worry that energized electrical wires could pose a threat of electrocution and that the floodwater could become contaminated with sewage and with toxic chemicals from industrial plants and backyard sheds. Gasoline, diesel fuel and oil leaking from underground storage tanks at service stations may also become a problem, corps officials say.

A variety of creatures -- rats, mice and nutria, poisonous snakes and alligators, fire ants, mosquitoes and abandoned cats and dogs -- will be searching for the same dry accommodations that people are using.

Contaminated food or water used for bathing, drinking and cooking could cause illnesses including salmonella, botulism, typhoid and hepatitis. Outbreaks of mosquito-borne dengue fever and encephalitis are likely, said Dr. James Diaz, director of the department of public health and preventive medicine at LSU School of Medicine in New Orleans.

"History will repeat itself," Diaz said. "My office overlooks one of the St. Louis cemeteries, where there are many graves of victims of yellow fever. Standing water in the subtropics is the breeding ground for mosquitoes."

910 mb!!! according to WWL 155 mph / 169 mph winds

What about that eyewall replacement thingies that goes on periodically? Is she due for one of those between now and lanfall?

Eyewall replacements happen all the time, 4-6 hours for a storm this size if I understand right from the weather bloggers. Projecting the replacements for landfall is all but impossible. Even if, according to the local station there, there is an eyewall replacement at JUST the right time, we're talking a disastrously strong Cat 4 --

Update: 910mb - a new low for the storm. Wow!