Hurricane Katrina - Category 5

[Blackhawk_996]

The Saffir-Simpson Hurricane Scale

Categories are 1 thru 5 - with 5 being the strongest storm

Category Five Hurricane:
Winds greater than 155 mph (135 kt or 249 km/hr). Storm surge generally greater than 18 ft above normal. Complete roof failure on many residences and industrial buildings. Some complete building failures with small utility buildings blown over or away. All shrubs, trees, and signs blown down. Complete destruction of mobile homes. Severe and extensive window and door damage. Low-lying escape routes are cut by rising water 3-5 hours before arrival of the center of the hurricane. Major damage to lower floors of all structures located less than 15 ft above sea level and within 500 yards of the shoreline. Massive evacuation of residential areas on low ground within 5-10 miles (8-16 km) of the shoreline may be required. Only 3 Category Five Hurricanes have made landfall in the United States since records began: The Labor Day Hurricane of 1935, Hurricane Camille (1969), and Hurricane Andrew in August, 1992. The 1935 Labor Day Hurricane struck the Florida Keys with a minimum pressure of 892 mb--the lowest pressure ever observed in the United States. Hurricane Camille struck the Mississippi Gulf Coast causing a 25-foot storm surge, which inundated Pass Christian. Hurricane Andrew of 1992 made landfall over southern Miami-Dade County, Florida causing 26.5 billion dollars in losses--the costliest hurricane on record. In addition, Hurricane Gilbert of 1988 was a Category Five hurricane at peak intensity and is the strongest Atlantic tropical cyclone on record with a minimum pressure of 888 mb.

Hurricane Katrina

Yesterday morning the National Hurricane Center cleared its throat and upgraded Katrina to a Category 5 hurricane -- the designation for storms capable of truly catastrophic damage and deadliness. That, however, wasn't the center's most significant statement. The real news was the center's chilling declaration that, at 902 millibars of internal barometric pressure -- the lowest barometric pressure ever recorded in the Gulf of Mexico -- Katrina was "comparable in intensity to Hurricane Camille of 1969 . . . only larger."

Those of us who lived though Hurricane Camille will never forget it. Camille struck with the force of several hydrogen bombs, altering forever the topography of the Mississippi coast. Its nearly 200-mph winds and 25-foot storm surge exploded concrete buildings and erased entire communities -- then gouged open graveyards and hung corpses in the live oaks like so much Spanish moss. There was a problem for a time telling the storm victims from those already embalmed.

More than 250 were dead before Camille swept up the Mississippi Valley as a tropical storm. Then, three days and 1,000 miles after it hit the coast, it took a right turn over West Virginia and, in some sort of terrifying meteorological joke, dumped 20 to 40 inches of rain in eight hours on Nelson County, Va., hosing away entire mountainsides, drowning or burying 150 more people and touching off 100-year-record floods in the James River basin.

Katrina, the National Hurricane Center said, is capable of more. Yet for a true New Orleans doomsday scenario, the storm's eye and strongest winds will have to thread a fairly precise path that carries its deadly northeast quadrant just east of the city. The real vulnerability of the city is not just that it's 10 to 15 feet below sea level, laced with more drainage canals than Venice, and must pump for its life around the clock in even the driest weather. Nor is the city's biggest problem the flown-in TV reporter's favorite specter of a hurricane storm surge up the Mississippi River that overtops the city's famous levees. That could theoretically happen, but it's less likely.

The real nightmare has always been the prospect of a Wagnerian hurricane like Katrina coming ashore so that its strongest winds push the Gulf of Mexico into the eastern-facing entrance to Lake Pontchartrain, which borders the city's northern edge. The lake is both unusually shallow -- rarely more than 20 feet deep -- and unusually large -- more than half the size of the state of Rhode Island. A 20-foot storm surge arriving in concert with both high tide and 20-inch rains could overwhelm the city's more vulnerable lakeside levees and then flow downhill all the way to the French Quarter. Many of the city's massive drainage pumps are located closer to the lake. Were they to be flooded out, the city would not only be helplessly inundated while the hurricane is overhead -- it would remain so for weeks if not months.

source -- The Washington Post

[Blackhawk_996]

By MATT CRENSON, AP National WriterSun Aug 28,11:23 PM ET


When Hurricane Katrina hits New Orleans on Monday, it could turn one of America's most charming cities into a vast cesspool tainted with toxic chemicals, human waste and even coffins released by floodwaters from the city's legendary cemeteries.

Experts have warned for years that the levees and pumps that usually keep New Orleans dry have no chance against a direct hit by a Category 5 storm.

That's exactly what Katrina was as it churned toward the city. With top winds of 160 mph and the power to lift sea level by as much as 28 feet above normal, the storm threatened an environmental disaster of biblical proportions, one that could leave more than 1 million people homeless.

"All indications are that this is absolutely worst-case scenario," Ivor van Heerden, deputy director of the Louisiana State University Hurricane Center, said Sunday afternoon.

The center's latest computer simulations indicate that by Tuesday, vast swaths of New Orleans could be under water up to 30 feet deep. In the French Quarter, the water could reach 20 feet, easily submerging the district's iconic cast-iron balconies and bars.

Estimates predict that 60 percent to 80 percent of the city's houses will be destroyed by wind. With the flood damage, most of the people who live in and around New Orleans could be homeless.

"We're talking about in essence having — in the continental United States — having a refugee camp of a million people," van Heerden said.

Aside from Hurricane Andrew, which struck Miami in 1992, forecasters have no experience with Category 5 hurricanes hitting densely populated areas.

"Hurricanes rarely sustain such extreme winds for much time. However we see no obvious large-scale effects to cause a substantial weakening the system and it is expected that the hurricane will be of Category 4 or 5 intensity when it reaches the coast," National Hurricane Center meteorologist Richard Pasch said.

As they raced to put meteorological instruments in Katrina's path Sunday, wind engineers had little idea what their equipment would record.

"We haven't seen something this big since we started the program," said Kurt Gurley, a University of Florida engineering professor. He works for the Florida Coastal Monitoring Program, which is in its seventh year of making detailed measurements of hurricane wind conditions using a set of mobile weather stations.

Experts have warned about New Orleans' vulnerability for years, chiefly because Louisiana has lost more than a million acres of coastal wetlands in the past seven decades. The vast patchwork of swamps and bayous south of the city serves as a buffer, partially absorbing the surge of water that a hurricane pushes ashore.

Experts have also warned that the ring of high levees around New Orleans, designed to protect the city from floodwaters coming down the Mississippi, will only make things worse in a powerful hurricane. Katrina is expected to push a 28-foot storm surge against the levees. Even if they hold, water will pour over their tops and begin filling the city as if it were a sinking canoe.

After the storm passes, the water will have nowhere to go.

In a few days, van Heerden predicts, emergency management officials are going to be wondering how to handle a giant stagnant pond contaminated with building debris, coffins, sewage and other hazardous materials.

"We're talking about an incredible environmental disaster," van Heerden said.

He puts much of the blame for New Orleans' dire situation on the very levee system that is designed to protect southern Louisiana from Mississippi River floods.



Before the levees were built, the river would top its banks during floods and wash through a maze of bayous and swamps, dropping fine-grained silt that nourished plants and kept the land just above sea level.

The levees "have literally starved our wetlands to death" by directing all of that precious silt out into the Gulf of Mexico, van Heerden said.

It has been 40 years since New Orleans faced a hurricane even comparable to Katrina. In 1965, Hurricane Betsy, a Category 3 storm, submerged some parts of the city to a depth of seven feet. Since then, the Big Easy has had nothing but near misses. In 1998, Hurricane Georges headed straight for New Orleans, then swerved at the last minute to strike Mississippi and Alabama. Hurricane Lili blew herself out at the mouth of the Mississippi in 2002. And last year's Hurricane Ivan obligingly curved to the east as it came ashore, barely grazing a grateful city.

[Blackhawk_996]

The absolute horrible part of this is so many people are stuck riding the storm out because they couldn't afford the gas to get out of town :(

Not really a religious person myself but godspeed to all that are in the path of this thing. And hopefully all the city's fair as well as possible.

[Snook]

All I know is you've got to be the Biggest Fucking Moron to give a name to such a Monster of a Hurricane....

[graham]

Katrina has just been downgraded to a category 4

[nightwind]

not to be pesimistic here but the difference between the cat 5 storm and what it is now is only five miles an hour drop in wind speed

my heart goes out to all the folks in the path of this storm and keep in mind the bands of this reach almost to memphis tenn already the big easy is in for a hit but so are many many others

[Dr Phil]

same here but its being said over here in nz that its still a 5 grade storm.

[wanker125]

Originally Posted by Blackhawk_996

Experts have warned about New Orleans' vulnerability for years, chiefly because Louisiana has lost more than a million acres of coastal wetlands in the past seven decades. The vast patchwork of swamps and bayous south of the city serves as a buffer, partially absorbing the surge of water that a hurricane pushes ashore.

Experts have also warned that the ring of high levees around New Orleans, designed to protect the city from floodwaters coming down the Mississippi, will only make things worse in a powerful hurricane. Katrina is expected to push a 28-foot storm surge against the levees. Even if they hold, water will pour over their tops and begin filling the city as if it were a sinking canoe.
He puts much of the blame for New Orleans' dire situation on the very levee system that is designed to protect southern Louisiana from Mississippi River floods.

Before the levees were built, the river would top its banks during floods and wash through a maze of bayous and swamps, dropping fine-grained silt that nourished plants and kept the land just above sea level.

The levees "have literally starved our wetlands to death" by directing all of that precious silt out into the Gulf of Mexico, van Heerden said.

this is what happens when people try to control nature. they may as well try to stop a volcano by filling it with cement. about as absurd. sucks to be those people down there, but what kind of denial have they been living in all these years? really, now -- isn't a good chunk of the city below sea level? had to happen eventually -- hurricanes have been around for thousands of years -- was just a matter of time.

[longhairedg79]

You guys need to keep in mind that this monster will not only affect those who lie in it's path, it will effect the whole US for sure. The price of gas will rise, the cost of food, ect...Within the next year taxes will go up as well, the nantional debt will increase do to the relief funding going to those states affected. I say god bless us all.

[Dr Phil]

i here an eraly estimate of the damage done is at LEAST 50 Billion and oil machine things were destroyed so now theres an excuse for the increase in petrol