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New wave off Africa ; New Orleans levees on hold

By: Dr. Jeff Masters, 7:09 PM GMT on July 13, 2006

A new area of concern has developed today off of the coast of Africa, 300 miles south-southwest of the Cape Verde Islands, at about 12N 25W. This large and well-organized tropical wave has developed a surface circulation, and is beginning to show some intense thunderstorms developing near its center. Wind shear is a marginal 10-20 knots over the wave, but is forecast to remain at this level or decrease some over the next two days. Sea surface temperatures are marginal for development, about 26-27 degrees C. There is some African dust to the wave's north, but not as much as we've been seeing in previous weeks. This wave could slowly organize into a tropical depression in the next day or two as it moves west-northwest at 15-20 mph. It's too early to speculate what the long-term track of this system might be. NHC is not impressed with this wave; they have not mentioned it in their 5:30 pm tropical outlook. No doubt the marginal SSTs and moderate wind shear--plus the fact that systems in this vicinity generally do not start developing until early August--are giving them a wait-and-see attitude.


Figure 1. Visible image of the Cape Verdes tropical wave. image credit: Navy Research Lab. Try animating this image from their web site to watch the wave spin up, and see the interesting eddies downwind of the islands off the coast of Africa.

Gulf of Mexico
Thunderstorms in the Gulf of Mexico near Key West, associated with a westward moving tropical wave, have decreased since this morning. Surface pressures are not falling, and no computer models are predicting that this area will be a future threat. However, wind shear is low enough to permit some slow development of this disturbance over the next day or two, so we'll have to keep an eye on it.


Figure 2. Latest satellite image of the Gulf of Mexico.

An upper level low pressure system is spinning over the western Gulf of Mexico. This low is expected to move ashore over Mexico by Friday without any tropical development occurring.

A tropical wave that moved through the Lesser Antilles Wednesday is in the eastern Caribbean. The wave has limited thunderstorm activty, and there is high wind shear and plenty of dry air in the eastern Caribbean. Development of this wave is unlikely.

Update on New Orleans flood protection
The Army Corps of Engineers has missed a July 9 deadline to complete new floodgates at the Lake Pontchartrain entrance to one of the drainage canals that flooded New Orleans during Katrina. No revised date has been set for the completion of the project. If a storm were to come now, the Army Corps would close off the canals using sheet pilings, as they did during Hurricane Rita. The new gates are designed to be closed when a hurricane threatens to bring a storm surge over five feet, and thereby keep waters from Lake Pontchartrain from flowing deep into the city along the drainage canals. It was the failure of the levees along these drainage canals that primarily responsible for the flooding of New Orleans during Katrina. However, closing the drainage canals means that the city will flood due to excessive rains, since it is these canals that take all the rainwater out of the below sea level areas of the city and dumps it into the Lake. (Thanks to wundermember mrpember for posting this info).

New Army Corps of Engineers report issued (repeat from this morning's blog)
A long awaited Army Corps of Engineers report on Louisiana coastal protection and restoration came out this week. The report had no specific recommendations on immediate actions to take to protect New Orleans from the next hurricane, saying another 18 months was needed to study the problem. Politicians and scientists immediately criticized the plan, saying that action is needed now. In particular, Governor Blanco of Louisiana and Louisiana's Senators were upset that five specific recommendations that they had agreed on with the Corps in May were stripped out of the proposal:

-- Beginning design work on a barrier and gate plan to protect the New Orleans area from major hurricanes.

-- Closing the Mississippi River-Gulf Outlet (MR-GO) to major ship traffic and beginning environmental restoration of the wetlands adjacent to it.

-- Design work on a plan for rebuilding eroded barrier islands and headlands and building new ones in the Barataria basin, which includes parts of Jefferson, Lafourche and Terrebonne parishes.

-- Authorizing the Morganza-to-Gulf hurricane levee project that stretches along much of the same area and has been awaiting congressional approval for several years.

-- Approval and financing for a variety of smaller restoration projects in southwestern Louisiana.

"These critical projects cannot wait another 18 months to be considered for action by Congress," Blanco said in a statement released Monday.

In the report, the Corps say they have completed emergency repairs to 169 miles of New Orleans levees, which are now as strong or stronger than before Hurricane Katrina. I can't tell from news reports what levee work--if any--is currently going on, I'd be interested to see if any of you know. In particular, is the $3 billion plan to move the pumping stations on the 17th Street Canal and London Avenue Canal to Lake Pontchartrain being worked on? It seems to me that this work is the most critical flood protection measure that needs to be undertaken.

Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Sorry supercell and imaghast, i'll try to move faster next time.
Hmm the Navy site is still calling 96L an invest:

Link

Bama Weather Watcher...I second the UUL sitting over Mobile Bay..We would get some of that over in Pensacola,and actually need lawn mowers again
oh yea lawn mowers....i remember those!!!
Sorry bama, my PC shut down!

Penn State model page
wow did one no how small bud is mean wow
508. mobal
What is a lawn mower? Is it something that picks up dirt and brown things in my yard?
Yes Taz it is extremely small.
aaahhhh!!! the wall...that page is confusing. Thanks i am trying learn to use that page. I know it has lots of useful info on it. Just don't know what it is!
Supercell, I would agree! I lived in Florida at the time of Andrew, but I didn't have to ride out that storm. I know those in his path was probably wondering if it was ever going to end. Stuff, like that, makes a person really pay attention to every blob that could possibly be the next big storm. I will say during Frances I was wondering when she was going to let up or fury on us.
Yeah bama it took me a little time to figure out where everything was.
Same here, with Frances, Jeanne, Andrew, Charley, and Erin in '95.
yea mobal...i think thats it! saw my neighbor with one the other day! almost put my eye out!
515. Alec
dont feed the bears....
I agree Supercell

Pensacola and Mobile are two of the wettest Cities in North America and we can't buy a sprinkle over here this summer..I remember it raining in the afternoon when I was a yearling
Yeah CB I remember that. Andrew broke a lot of "rules".
520. mobal
Oh bama, One must use care around such beast as lawn mowers...LOL...night all
521. Lane
I want to thank all of you guys for watching every little disturbance the developes in the atlantic basin. I live in southeast Louisiana, and was in the western eyewall of Katrina. I would hope nothing forms in out there, but we all know something will sooner or later. I check these blogs daily. I hear about tropical weather here way before i hear about it from anywhere else
522. mobal
Hi Alec!
523. Alec
hello mobal........just read a few pages of this blog...
Lane,

sometimes ya hear about tropical weather that isn't...But as a whole these guys decipher info pretty good..
record show only 135mph. But that was back in 79 before our technology really started to get better.
Thanks for checking in Lane, everyone here is happy to help. I hope Katrina didn't do too much to you and yours.

Ya talking about frederick bama?

september 12th,1979
529. mobal
Alec, Yea...well im off...good night to all
530. Alec
night mobal.....cyclone, I suppose I should build a tunnel down my throat to help the food go down as well.....LOL..........Night all!=)
Good night mobal.
yes rolltide...were you around for it? It was a couple of years before my time. Im just going off what I learned in my MET class at USA.
Good night Alec.
Lots of pretty lightning to the north but it may not get here :(

(Probably Alec's fault...)

Wait.... did I hear thunder?

I Lived in Flomaton,al during Frederick..was real Young but that sucker was a bad boy,sucked all the water out of mobile bay.

I imagine if ya went to South Alabama ya heard about it a Freddy a time or two
Yes they like to talk about it out there. Well i need to go to sleep. Rolltide check out my blog and let me know what you think. Just some stuff about Dennis from last year.

have a great night All!
Good night bama.
I believe the university opened soon after the 1926 Miami Hurricane, and so they decided to call the team name the Hurricanes.
All should take a break for a week or two, nothing happening, night all.
ProgressivePulse - That sounds like some good advice. Get some rest, and prepare. Good night.
i dont know about that cyclone buster it might just get killed by the shear before it can come back
that wave off the africa coast is the one too watch
Looks like both the NOGAPS and the CMC models are forecasting a system to form near the Yucatan and cross into the Bay of Campeche and threaten NE Mexico or south Texas.
The wave in the Eastern Atlantic has lost alot of its convection tonight...
The wave is dealing with both dry air and eastly shear now, and SST's are hardly high enough They are around 26.5c...Which is very little to burst the dry air layer. adrian





2:05 am discussion from the NHC.

AN ATLANTIC OCEAN TROPICAL WAVE JUST HAS CLEARED THE CAPE VERDE
ISLANDS AND IS ALONG 26W/28W SOUTH OF 17N MOVING WEST 15 KT.
CLEAR EVIDENCE OF CYCLONIC TURNING SHOWS UP IN CURRENT INFRARED
SATELLITE IMAGERY FROM 10N TO 14N BETWEEN 25W AND 31W. WIDELY
SCATTERED MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS OCCUR
FROM 10N TO 13N BETWEEN 27W AND 30W.
good morning everyone
I think I see a swirl starting at 85/24

or, do i just need another cup of coffee?
I noticed the Canadian has a tropical storm (I think a regenerated former 96L, now looking quite pitiful) aimed at Brownsville next Wednesday evening.


of course, in a world that was like the Canadian, we'd have 30 tropical cyclones every year.
GFS looks nothing like the Canadian, but the NOGAPS (looked at it for grits and shins) is like the Canadian, but a bit weaker and further South Wednesday evening.
Stormy - definately looks like a swirl, but I'm not sure what it means.
Stormy, I think that swirl in the Gulf is an upper level low that has been there a couple of days (or at least yesterday) until it is a lower level low we are ok..

WOW, did I just sound like a "weather geek" or what!!!


I read back a little but does anyone have any new information about that wave off Africa yesterday? Will check back on my next break for any info you may leave!
Have a great Friday!
In my very unexpert opinion, but based on some experience, little low cloud swirls in the GOMEX aren't super-unusual, and unless it has thunderstorms, doesn't mean much.

I guess ince it is a slow day, and not much is happening, I'll check back on the little swirl just off the Northwest tip of Cuba, that seems to have fired up a thunderstorm, but I have a feeling it will be a slow day.

But it is still the first half of July.
seflagamma - LOL, you didn't sound like a weather geek ...you have to start using acronyms for everything you state before you get that classification! :-)

Thanks for the clarification ...I don't want to see anything swirling this close to home.
Unrelated to the tropics, but I spent a summer here. High temp in Monahans, TX forecast at 111F
Ed ...that is my little swirl - your picture is prettier though. :-) there are tstorms to the east-north east but maybe those are just a fluke. shear doesn't look high in that area ...but i'm not good with the model maps so I'm probably looking at shear forecasts for august...
Hey everyone, Dr Masters has new blog up .

I'm fairly new at looking at these things, but does that big red blob coming off the north of South America into the Caribbean mean anything? On the IR loop, I see a black center surrounded by a bunch of red, but maybe it's just a lot of clouds/storms unrelated to tropical development.
god bless texas (you made me break out into song).

I spent a lot of time working in texas a few years back - folks are way nice but weather is horrid. Although, I dreaded the trips to Phoenix much more than texas ...Phoenix exists because the settlers' horses died of heat exhaustion before they could get to a better place ...so they had to stop and build a city.

(...phoenix folks, don't send me hate mail - I'm kidding! It is a lovely place if you prefer multiple shades of brown!)