Katrina is gone

By: Dr. Jeff Masters , 6:56 PM GMT on August 31, 2005

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Katrina lost its tropical characteristics this morning and is no longer a tropical depression, just a regular low presssure system. She continues to dump 2 - 4 inches of rain along her path, and is a threat to bring minor flooding to northern New England today and tomorrow. Katrina-spawned tornadoes killed two in Georgia and damaged 13 homes in Marshall, Virginia yesterday, but the threat of tornadoes has diminished today. Katrina is no more, a blessing we can use right now!

Blessings are very hard to find in the catastrophe zones of Louisiana and Mississippi today. We are only just now beginning to hear from the areas that the calm of the eye passed over. Slidell, on the western side of the eye's passage, received a 15-foot storm surge. Only foundations are left of a large portion of the buildings, and the bridge to New Orleans is broken in multiple places, according to news reports. Pass Christian, unlucky holders of the U.S. record-highest storm surge of 24.7 feet from 1969's Hurricane Camille, received a 20-foot storm surge. The storm surge at nearby Bay St. Louis was 22 feet, and both areas have extensive areas of complete destruction.

Why did the New Orleans flood walls fail?
The 325-mile long series of flood walls and levees surrounding New Orleans were engineered to withstand the storm surge from a Category 3 hurricane. No Category 3 or higher hurricane has hit New Orleans in the past 150 years, a strange quirk one would not expect based on the pattern of hurricane strikes elsewhere along the Gulf Coast. New Orleans should get a Category 3 hurricane passing within 80 miles every 32 years, a Category 4 hurricane every 70 years, and a Category 5 hurricane every 180 years. However, the strongest hurricanes ever to hit the city were two Category 2 hurricanes--a 1893 hurricane that killed 2000, and Hurricane Betsy of 1965, which killed 75 and put parts of the city under 8 feet of water. Hurricane Camille, although it was a Category 5 hurricane and took almost the same track as Katrina, was a very small hurricane with hurricane force winds extending out only about 50 miles from the center. Camille brought 100 mph gusts to the eastern side of New Orleans. Katrina was a huge storm whose hurricane force winds extended a full 110 miles from the center, and probably brought 130 mph wind gusts to the same area. Katrina piled up a much larger storm surge wave onto the flood walls than Camille. According to the Army Corps of Engineers, "What failed were actually floodwalls, not levees. This was caused by overtopping which caused scouring, or an eating away of the earthen support, which then basically undermined the wall. These walls and levees were designed to withstand a fast moving category 3 hurricane. Katrina was a strong 4 at landfall, and conditions exceeded the design." The flood wall breaks lie along Lake Pontchartrain, whose water is 4.5 feet above sea level. Thus, since New Orleans lies 6 feet below sea level, we can expect the city to flood to a depth of at least 10 feet.

I highly recommend reading an October 2001 article from Scientific American, titled: Drowning New Orleans, to learn more about the vulnerabilities of the levee system.

The tropics today
The most significant threat in the tropics I can see is the potential this weekend for a tropical depression to develop in the coastal waters surrounding Florida. This is the same location that Katrina developed. However, this time the development might come at the tail end of a cold front that is expected to push off of the East Coast, instead of from a tropical wave. If a depression does form in this area, the possible track is impossible to guess at this point.

Tropical Depression 13 is nothing to worry about, as it is over the open Atlantic Ocean and heading out to sea. The well-organized wave 1300 miles east of the Lesser Antilles will probably become Tropical Depression 14 in the next day or two, but it is probably too far north to threaten any land areas. This system will probably recurve out to sea. The tropical wave that pushed off of the coast of Africa yesterday and is now south of the Cape Verdes Islands has some potential for development later in the week, and the GFS model projects that this wave will become a hurricane and a potential threat to the Leeward Islands a week or so from now.

On August 19, I posted the image below showing a long-range forecast for August 31 from the GFS model.

As you recall, mid-August was a time of relative quiet in the tropics, but the GFS model was calling for an end to this quiet period. The 12-day GFS forecast called for 3 tropical cyclones for August 31. Well, the GFS was correct in calling for an end to the quiet period! While there is only one tropical cyclone (TD 13) out there, the other two strong tropical waves seen in the satellite image above certainly have the potential to become tropical depressions over the next few days. The GFS did miss the formation of Katrina, but the general 12 day forecast showing a big increase in hurricane activity was pretty accurate.

Dr. Jeff Masters

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743. leftyy420
4:04 AM GMT on September 01, 2005
prior to today the price had only gone up 2 cents since last week.
Member Since: August 24, 2005 Posts: 35 Comments: 1987
742. StormJunkie
4:05 AM GMT on September 01, 2005
It is just going to get worse Lefty.
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741. StormJunkie
4:04 AM GMT on September 01, 2005
Headed home from work will be back in a little bit.
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740. leftyy420
4:03 AM GMT on September 01, 2005
my wife just pain 2.90 for fas in va. thats the first time sincew io have had a car i have ever paid more than the national avg. thats a 40 cents increas in one day. just letting yall know bout how it is here in va
Member Since: August 24, 2005 Posts: 35 Comments: 1987
739. StormJunkie
4:02 AM GMT on September 01, 2005
Have not heard from Stormtop. I am not sure who elese you were wondering about Cajun. Orleans 77 Evaced to NY so he is safe.
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738. bekroweather
3:59 AM GMT on September 01, 2005
Yeah, are there any news from STORMTOP?
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737. COobserver
3:32 AM GMT on September 01, 2005
This article is infuriating to read...



"In early 2004, as the cost of the conflict in Iraq soared, President Bush proposed spending less than 20 percent of what the Corps said was needed for Lake Pontchartrain, according to a Feb. 16, 2004, article, in New Orleans CityBusiness."

"The 2004 hurricane season was the worst in decades. In spite of that, the federal government came back this spring with the steepest reduction in hurricane and flood-control funding for New Orleans in history. Because of the proposed cuts, the Corps office there imposed a hiring freeze. Officials said that money targeted for the SELA project -- $10.4 million, down from $36.5 million -- was not enough to start any new jobs."

"One project that a contractor had been racing to finish this summer: a bridge and levee job right at the 17th Street Canal, site of the main breach on Monday."

"The Newhouse News Service article published Tuesday night observed, "The Louisiana congressional delegation urged Congress earlier this year to dedicate a stream of federal money to Louisiana's coast, only to be opposed by the White House. ... In its budget, the Bush administration proposed a significant reduction in funding for southeast Louisiana's chief hurricane protection project. Bush proposed $10.4 million, a sixth of what local officials say they need."
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736. cajunkid
3:53 AM GMT on September 01, 2005
all the apartments and house in baton rouge that were for sale are going fast, I have been trying to find a place for my girlfriends family to rent and its impossible
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735. cajunkid
3:51 AM GMT on September 01, 2005
stormjunkie, where is everone and are they ok
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734. DubbyaCU
11:50 PM EDT on August 31, 2005
I am not a DEDICATED one but I am around from time to time and grew close to many of you guys and feel much like family. So, I was wondering if there is yet word on STORMTOP?

- C
733. StormJunkie
3:43 AM GMT on September 01, 2005
Glad you are ok Cajun and Hurry. My thoughts and prayers are with ya'll.
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732. cajunkid
3:37 AM GMT on September 01, 2005
hi, still don't have power so I haven't been on here since 4am the of it. oreleans77 and lefty, man I thought we might have dodged the bullett @ 4am when it looked like the west side died out a little, but you all know what happened. My prayers are with all of you!
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731. HurryCane
3:35 AM GMT on September 01, 2005
I still have a home on the gulf coast of Mississippi, thank God. I lost 18 trees and will have to replace some carpet. I am so blessed, but my city and my way of life as I knew it are over. And I have seen and experienced things, no one should ever. I am just here for a minute but will write a blog of my own tomorrow. I just arrived in Atlanta as there is no water for bathing and flushing at my house. I have a big generator, but it doesn't provide water. I will also post some horrendous pictures soon. Please pray for the area, almost no one I know still has a home. And the thieves are disgusting.
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730. cgableshurrycanegal
11:29 PM EDT on August 31, 2005
it's dog-walk time, then sleepy-time, so calling it quits,
nighters all.
Member Since: July 12, 2005 Posts: 24 Comments: 214
729. cgableshurrycanegal
11:27 PM EDT on August 31, 2005
no mention locally of a possibility of something stewing off that trough... just that we might have rain SUN-TUES...
Member Since: July 12, 2005 Posts: 24 Comments: 214
728. cgableshurrycanegal
11:23 PM EDT on August 31, 2005
great. local weather teaser is that we're in for a soggy weekend. didn't we just do that? ARGH!!!
Member Since: July 12, 2005 Posts: 24 Comments: 214
724. cgableshurrycanegal
11:16 PM EDT on August 31, 2005
sorry, jeff, but I think you crossed the line here.
this blog was definitely not going down religious discussions and I for one don't think it is intended as such. Intelligent design could create a whole new dimension on how and why Katrina even HAPPENED... so don't lets go there.
One's beliefs are personal, and I'm not about to discuss mine here where I don't know any of you well enough to consider it your business to think you might feel you could stand in judgement of me if I don;t conform to whatever standards you deem approprite. enough said.
Member Since: July 12, 2005 Posts: 24 Comments: 214
723. Orleans77
3:18 AM GMT on September 01, 2005
with that said..im turning in for the night ..i do pray that the lord will ease the terrible suffering of the survivors, will bless the soul of those who have departed us and will comfort their lovd ones...
721. leftyy420
3:17 AM GMT on September 01, 2005
refugees turned up at the astrodome and they turned them away. right now they can get a meal at a shelter but have no roof to sleep under. they are only going to use the astrodome for those peoplein the superdome. this is bs. the govt of la needs tofind shelters for evryone and send them there. 200,000+ left in nola might need sheltewr. where do they go. only 25,000 can get into the astrodome. this is a joke
Member Since: August 24, 2005 Posts: 35 Comments: 1987
719. OBXER
3:15 AM GMT on September 01, 2005
CG i really gotta go but the abaco thing is i have a house on Green Turtle Cay in the abacos
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716. cgableshurrycanegal
11:14 PM EDT on August 31, 2005
OX, thought you left, why abaco?
Member Since: July 12, 2005 Posts: 24 Comments: 214
715. cgableshurrycanegal
11:13 PM EDT on August 31, 2005
damn. Lee is already back down to td
Member Since: July 12, 2005 Posts: 24 Comments: 214
714. marinetech43
3:09 AM GMT on September 01, 2005
Was talking to some guys at work, including the boss, about the refugees. Here, in New Iberia, when we see a family of refugees, we will offer to buy them a meal. Just a very small help to them in a very bad situation.
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713. OBXER
3:07 AM GMT on September 01, 2005
Hey just a dumb question before i really do leave but it oseems like this board has brought a wholelot of people together from all over the states that have a common interest in whats going on and i dont know how you can make a friend over the internet but i feel like i have a few more.goodnight everyone and thank you and lets hope tomorrow is better than today
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707. Orleans77
3:09 AM GMT on September 01, 2005
ur right except the Pres did what he could he throwing everything the feds have at the problem...he actually wanted to visit but decided to wait until rescue efforts are done as he does not want to interfere with rescue efforts due to security his visit would require...besides what can he really say,...htis is such a bad disaster...plus it comes at an awful time for him...his polls are already so low...this does not help
705. leftyy420
3:09 AM GMT on September 01, 2005
i feel ya 77
Member Since: August 24, 2005 Posts: 35 Comments: 1987
704. Orleans77
3:06 AM GMT on September 01, 2005
maybe in the short term...but in the long term it woudl energize us to fight for our country...u cant keep America down...we are the beacon of the world...im hearing from my friends overseas...that there is shock and worry all over the world...the world is not used to seeing America on its knees like this...as much as some hate us the world relies on us as a beacon for democracy and a beacon of hope..when they see us down like this the world get scared....
703. cgableshurrycanegal
11:04 PM EDT on August 31, 2005
know what you mean, here we are enjoying our creature comforts and these folks in NO and other areas are praying for the most basic of needs.
And frankly, the pres said absolutely nothing, why did he waste air time?
Member Since: July 12, 2005 Posts: 24 Comments: 214
702. Orleans77
3:05 AM GMT on September 01, 2005
thank you oxber ..jus remember the good Lord does not give us more than we can handle...sometimes i just wish he didnt think I was so strong...:-)
701. leftyy420
3:04 AM GMT on September 01, 2005
yeah 77. a attack now could break our spirit. we are gonna be pasying incredible prices at the pump atleast for the next week. its rough
Member Since: August 24, 2005 Posts: 35 Comments: 1987
700. OBXER
3:00 AM GMT on September 01, 2005
Orleans 77 i caught your last post before i left and i am so sorry that your friend didnt make it.I really appreciate the updates thqat you posted while dealing with this and if you need any help that i can provide my email is on the board.Life sucks sometime but hopefully we can all learn from this.
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699. Orleans77
3:04 AM GMT on September 01, 2005
some are like that...real scum..sorry i know thats harsh but tell it like i see it
698. Orleans77
3:03 AM GMT on September 01, 2005
i told him earlier gable and rathe than admit he was wrong he said i wanted it to happen and was gleeful so many died..hes a loser class A
697. cgableshurrycanegal
11:03 PM EDT on August 31, 2005
orleans, I've been wondering the same thing.
kick 'em while they're down...
Member Since: July 12, 2005 Posts: 24 Comments: 214
696. Orleans77
3:02 AM GMT on September 01, 2005
thks gable..just wanted to state what i lost while certain people here who have lost nothing slam and defame me...that said i have my life tonight, a full stomach, electric and i am able to take a shower...i am very very fortunate
695. cgableshurrycanegal
11:01 PM EDT on August 31, 2005
local ABC affiliate is stating that estimate of death is numbering in the thousands, wonder if squam is still up and watching WPLG... hmmmmmm.....
Member Since: July 12, 2005 Posts: 24 Comments: 214
694. Orleans77
2:59 AM GMT on September 01, 2005
ill tell you what scares me most for the future...we as a nation are incredibly vulnerable...this would be the "ideal" time for our enemies to hit us...one more terrorist attack, one more regional conflict and we will have to have a draft....we are very very vulnerable and if our millitary wasnt stretched before they are now...i support everything we are doing, including Iraq -- just think these are very dangerous times for our nation
693. cgableshurrycanegal
10:59 PM EDT on August 31, 2005
orleans, that so sucks.
a dear friend was registering her god-daughter at Tulane, oh well, they're all back in TX...
That is nothing in comparison with your losses...
Member Since: July 12, 2005 Posts: 24 Comments: 214

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Dr. Masters co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters from 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

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