WunderBlog Archive » Category 6™

Category 6 has moved! See the latest from Dr. Jeff Masters and Bob Henson here.

Caribbean disturbance slowly developing

By: Dr. Jeff Masters, 1:37 PM GMT on September 26, 2005

Caribbean tropical disturbance
The main area of concern today is a tropical disturbance in the Caribbean sea, south of Hispanolia. Surface pressures have started to fall in association with this disturbance, and deep convection has slowly increased the past 12 hours. Wind shear values have increased this morning over the leading (western) portion of the disturbance, and are now about 10 knots, which is only marginally favorable for a tropical depression to form. The trailing (eastern) portion of the disturbance south of Puerto Rico has less shear (5 - 10 knots) over it, and this portion of the disturbance is showing the greatest growth in deep convection this afternoon. The shear is forecast to to remain constant or decrease over the next 48 hours as the disturbance tracks west-northwest at 15 mph. There are currently no signs of a surface circulation, and the disturbance is still relatively small and disorganized, so it is not expected to develop into a tropical depression today. A reconnaissance airplane is scheduled to visit the area on Tuesday.

An upper-level low pressure system over Cuba is forecast to weaken and move northwards during the next three days, which would lessen the shear over the disturbance and steer it more to the northwest, as seen in the early track model forecast from the BAMM model, shown below. I give this disturbance a 60% chance of becoming a tropical storm by Thursday. However, the upper level winds are far from ideal for a tropical storm, and this system may struggle to survive if it does manage to form.

Mid-Atlantic disturbance
A tropical disturbance located about 1200 miles east of the Lesser Antilles remains poorly organized, and is suffering from wind shear imparted by a large upper-level low pressure system to its west. Development of this disturbance is not expected for the next two days.

Elsewhere in the tropics
Long range models show the possibility of more tropical development off the coast of Africa during the week, as well as the Caribbean and Gulf of Mexico. We still have about three weeks remaining of the peak period of hurricane season, and I expect two or three more tropical storms will form between now and mid-October.

I mentioned in my blog yesterday how Port Arthur got a direct hit by the eye or Rita, but escaped catastropic storm surge damage. The image below, constructed by NOAA's Hurricane Research Division based on data taken by the NOAA hurricane hunter aircraft, confirms that this occurred because the east eyewall of Rita with its powerful southerly winds never blew over the bay Port Arthur lies on. Thus, water from the open ocean was not forced up into the bay by the eyewall's winds. The maximum storm surge hit a very sparsely populated area of the Southwest Louisiana coast. The small town of Cameron (population 2000) was the largest town along this stretch of coast, and suffered damage similar to what was seen in Mississippi from Hurricane Katrina. The winds of the east side of the eyewall made landfall due south of Lake Charles, pushing the worst storm surge up to that city.

Figure 2. Winds of Rita at landfall as measured by the Stepped Frequency Microwave Radiometer (SFMR) instrument on the NOAA hurricane hunter aircraft.

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

3 things

1. So the race is on between the quickly cooling waters and the names left in the hurricane pool, will we see a tropical system Alpha?

2. Usual plug about posting hurricane related links to my blog

And mucho thanks for those that posted

3. Saw Christmas stuff for sell at Target yesterday, Am I a old fuddy duddy in my believe Christmas stuff should not come out until after Thanksgiving (also remenber Halloween candy was out in mid-august, I saw WalMart actually clearing school supplies out for it)
Highly doubtful, but I find it interesting that the GFDL takes Rita back into the gulf. Like I said, I think it is very unlikely but just an interesting observation.

I was wondering if Rita was going to pull an Ivan....same thing, rain one way, circulation another.
Looking at visible loop, you can see what is left of the circulation heading down toward the gulf
I think these are the early links to what could be TD19/Stan:


Dr. Masters, given the combination of shear and the lower gulf temps, what are the chances of this becoming another 4 or 5? The GFS has this going over Louisiana but that's pretty much guesswork at this point. Can you give a little more detailed discussion on how strong this thing should get, where it's most likely to go, and why?
Hello everyone .......Im in Florida......No more Hurricanes for Louisiana.......Its somebody elses turn......We need to spread the love.......as far as future storms and can the gulf support another cat 5 is a very hard question to answer.....I think it could....anything is possible......you have to remember that the warm water is only one facet of many ......the atmospheric conditions can make or brake a storm.....I think a storm that sits in one area to long would be affected....as far as a storm that comes from the caribbean or even the bahamas as katrina and rita did could survive if it were moving at a decent rate, provided that the atmosphere were in good condition to support it........look at this season.....to cat 5 in july in less than optimum conditions "normally".....As Dr. Masters has said........."this is the hurricane season of 2005"......the caribbean is primed and ready to go.....a storm like charleys path would have no problem hitting florida as a major storm......and thats my opinion......look at its path if that were to happen right now.....the only waters that would be affecting it would be between cuba and florida....the waters along the florida west coast have not been affected all that bad.......as always...time will tell.....
Though the BAMM run is not terribly accurate beyond 24-36 hours, my own untrained eyes see nothing in the Caribean basin to slow a potential TD19/Stan down. The lower temps in the gulf may not support another Cat 4 or 5, but any tropical system would wreak havok on the gulf coast at this time. I don't think LA could take another system, even a Cat 1, without severly stressing the current relief efforts. Just my opinion...
SaCaHa, Saw the same thing.
The Pandhandle Swirl looks like the remnants of Ivan we handle Last Year.
Ivan Remnants reformed circulation offshore E Coast Florida near Brevard/Indian River Countys. Dumped 8" of Rain on us 5 days before Jeanne hit.Remember hearing that NHC has a policy of not classifing a TD When Circulation forms over land, the expectation is that a budding storm won't survive over land mass for more than 6-12 hours with out water/rocket fuel. Ivan Track
They Were Wrong About Post-Ivan, he survived & was re-classified when re-entered the Gulf of Mexico. Folks here were cleaning up & blue tarping from Frances & had no idea what was happening. Media was clueless.
Sorry, missed link:Ivan 2004 Track
Check out Hillsbouroughs Blog. Very good blob tracker, its worth looking at.
Nice wave, Stan!
If you have been listening to the NHC....you need 80 degrees to maintain a hurricane.....the key word "MAINTAIN"......if a hurricane comes from the caribbean at cat 4 or 5 status and is moving at 10mph or more....I think it would have no problem maintaining.....intensifying would be a different story....we already have had for major hurricanes run thru the gulf....dennis, emily, katrina, and rita....granted that emily did not officially make a US landfall it did move through the gulf....at any rate, no one thought that rita could get to the status that it did and in the same area that katrina fired up......and right now its 90 plus at my home right now.......so im guessing its pretty hot in the gulf right now.......
I have been watching that wave that enterered into the Carribbean over last couple of days. It looks like it split into two pieces. Does the board think that the Western half is just a one-day flare up with the convention being with the Eastern piece? I am just trying to figure out if this is one system or two separate systems now.
Yes, I can see Rita remmants about to come off the coast of FL...question is, will it form into anything? Are conditions favorable in the gulf? Anyone know?
FLCrackerGirl...I remember Ivan last year coming back at us, I am in Brevard county. I kept telling everyone here at work that all of the rain was from Ivan, and no one believed me.
Gainseville, Rita and Katrina were both double blobs that formed only 1 t.s. off the FL coast...I'd assume that if one formed, it would suck the convection from the other into its system.
Link Here is rita remmants
Hey Stormy, hey all... Rainy here in Pcola
I wonder if the heat wave over the central gulf coast and texas is being increased by the heat released by all the condensing water from Rita.
Ya 21, thats Rita saying hello. lol
anyone think that the remmants of rita will turn in to something when it hits the golf
Simon, Ive noticed that after a hurricane rolls through, its extremely hot...maybe cause I experienced it with lack of AC after Charlie, Frances, and Jeanne...and I remember hearing how hot it was after Kat over the in N.O.....its kind of like a punishment, it seems, lots of rain...then lots of heat!
lol, yeah Stormy
My opinion on Rita - Conditions seem favorable right off the gulf coast of FL as long as she doesn't move too far south...there is an upper level low on the s/e coast of FL Link that would cause a lot of shear....
Where can I find the Hillsborough Blog?
visible loop of Ritas remnants

kind of boring blog today...so let me add some interesting info I found in "The Handy Weather Answer Book" published by Walter Lyons in 1997...
always looking for interesting info, so go ahead stormy
That sounds good Stormy =)

For You Pen21 - ? states "which area is luckiest in terms of avoiding hurricane strikes?" Perhaps the luckiest are so far in dodging the hurricane bullet is Pensacola, FL....
Mind you, this was written in 1997...
Some other things.....
ok 65 for us, same ? Luckiest, next sentence read....The region around the Kennedy Space Center has also been spared for most of the twentieth century.
Now, this statement still holds true...
I have some more too...
Tallahassee has been REALLY lucky so far...
What was the earliest an Atlantic hurricane has formed? The ealiest hurricane of the year was March 7, 1908 Link, but the hurricane season got off to an early exceptionally early start in 1955, with the first hurricane occurring on 2 January Link (this one was recorded in 1954)
But, wait, theres more...
I would think the luckiest state would be Georgia... depending on how far up the east go you go.
Hey, Stormy. Pretty interesting book. Does it say anything about Ft. Lauderdale? We have had the outside edges of a lot of systems but no direct hits for a long time.
Can't prove this one from wundergrounds site...
What was the "Storm that wouldn't die"? Super Typhoon Gay, in late Nov 1992, travled across thousands of miles of the Pacific with winds up to 225 mph. Its remnants then formed into a massive storm off the Aleutian Islands (Alaska area). After reforming again in British Columbia and crossing California, it gave birht to another low in Texas that became a great Northeast storm along the US East Coast with wind gusts reaching 90mph on December 11, 1992.
Want some more?
More! More!
re typhoon gay. Link
What year had the most hurricanes in the Atlantic Basin? The most avtive year for full blown hurricanes anywhere in the North Atantic, Caribbean, or Gulf of Mexico was 1969. In that year, a doxem storms reached full hurricane strengthed. Only in 1907 & 1914 did any sotm fail to reach hurricane force. Will we beat the record this year for the most hurricanes...? We are up to 9 so far...
I say yes we will. Been having a couple in late Oct.-Nov. the last few years.
Tallywatcher -under my luckiest area ?, the last part of the paragraph said: The Miami area had ben doing well since Donna in 1960, until Andrew came along in 1992. But not far away, two destructive hurricanes in just nine days struck the Apalochicola-Tallahassee, Florida, region.
Thats it for luckiest question...It didn't reference any dates for the Tallahassee ones...
Here is a link (a little outdated) that compares Powerful Hurricanes and Typhoons

I don't know either. I've only been in Tallahassee for 6 years.
thanks for the link Coconut, but no, the book doesn't say anything reg. Ft Lauderdale...sorry
Of course, the deadliest hurricane on US Mainland still exists, it was the 1900 hurricane of Galveston, TX...we've heard plenty of that one since Rita headed that way. Says: At least 6000 perished, according to the official report. There is evidence that the actual death toll may have been as high as 8000-12000 people. This storm single handedly made September the deadliest month of the calender for hurricane related deaths in the United States.
Oh, more on Florida (remember, this is dated 1997, so doesn't include last years storms)
How deadly are Florida Hurricanes?
Florida has suffered three of the five deadliest US Hurricanes of this century. In 1928, a hurricane crossing Lake Okeechobee took 1,836 lives. Six hundred were lost in a 1919 storm and 408 perished in the violent storm that swept across the Keys in the 1936.
Didn't the Keys have their grotto by then? Id have to go back and look thru Masters blogs unless any of you remember???
floater 1 has been repositioned over the disturbance in the Caribbean
What are the most hurricane-prone parts of the U.S. coastline?
According to climatology, the areas of the nation most likely to feel the impacts of hurricanes are the sourhtern tip of Florida, the outer banks of North Carolina, and the upper Texas Gulf coast into Louisana.
Okay, this is the final one that I found interesting, then Im done...
Do hurricanes affect the coastline?
Yes, and quite literally. In 1853, a barrier island called Isle Derniere off the Lousiana coastline was split into four segments by a hurricane. Scientists studying these reapidlyeroding islands thought that at least two of the Isles Dernieres would disappear between 2001 and 2006. Then came Hurricane Andrew contributing mightily to the islands erosion.
NOTE-does anyone know if its still there now?
Several of the inlest and cuts in the Outer Banks of North Carolina were carved by passing hurricanes during the last 150 years. Sediment cores from Florida's west coast indicate huge freshwater floods during strong hurricanes more than a thousands years ago. Geologists have found layers of sediment in an Alabama lake that were probably carried inland by intense hurricanes some 3,000 years ago.
Amazing, isn't it???
Here's one:
Hurricane direct hits on the mainland for individual states 1851-2004 by Saffir/Simpson category. Top 3
Florida with 110 35 of those CAT 3-5
Texas with 59 19 of those CAT 3-5
Louisiana with 49 18 of those CAT 3-5
North Carolina is a close 4th with 46 and 12 of those CAT 3-5
State with the least? Pennsylvania with 1


If I remenber correctly the grotto was deicated to the ones that lost thier lives in the Labor Day Hurricane.

Also you other post brings up a interesting concept that what is thier are bigger cycles at play and the intense hurricanes we know will look like mere babes compared to some of the hurricanes in earth's long history.
Weatherdude - so, that would mean that the percentage of Cat 3-5 squalls that hit each state would be:

Florida 31%
Texas 32%
Louisiana 37%
N. Carolina 26%

Interesting stuff...........