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TABASCO served in the GOM and 90L is declared!

By: moonlightcowboy, 12:55 AM GMT on August 10, 2007

SPECIAL PRE-TEXT- LOWERCAL's blog has an interesting topic about this weekend's "meteor shower" and some great links to space shuttle Endeavor's current mission. Check it out!

NOW, ON TO THE TROPICS!

SSTs3.gif picture by moonlightcowboy

Gulf Waters Are "TABASCO" Hot!
Metaphorically, the GOM is just that hot! And, if you've ever dined in a southern restaurant, one knows that the little bottle of fire that sits on the table is legendary because of its heat! A friend of mine buys it by the gallon and puts it on nearly everything, including eggs and cole slaw. Of course, I like it, too; but not on everything (lol). It's not too ironic that the fiery product hales from Louisiana almost right on the GOM at Avery Island about a 100 miles west of NOLA.

And while Tabasco can heat up our foods, Gulf waters also heat up our hurricanes! The GOM's hot waters are "pure fuel" for rapid intensification. These storms need two basic ingredients to develop: warm, moist air and a relatively calm atmosphere. The GOM does just that as we saw in 2005 with Katrina. Ocean waters above about 27 degrees Celsius (80 Fahrenheit) give rise to the warm, moist air that fuels tropical storms, and winds that could tear a storm apart are light during the summer. Waters are 86 degrees and warmer now, with much of the GOM even in the 90's. Typically, the GOM's waters are hot even at the beginning of hurricane season, while it generally is August before the Atlantic is primed.

This image above shows sea surface temperatures in the Atlantic, Caribbean and the Gulf of Mexico. Water that is warm enough to fuel hurricanes is yellow, orange, and red. So, as you can see the relatively shallow Gulf of Mexico and the Caribbean are quite hurricane-ready! And, unfortunately, can turn an already bad storm into a monster!
Actual SST link for graphic above.


THE NATIONAL BUOY CENTER - an excellent site for checking on-the-spot GOM and Caribbean SST's, pressure and winds.

http://www.aoml.noaa.gov/phod/dataphod1/work/HHP/NEW/2007220ca.jpg

TCHP = TROPICAL CYCLONE HEAT POTENTIAL These "boiler" ingredients could create a dangerous situation if a storms tracks through these deep, hot waters which are more serious than the 2005 season.
--- TCHP from Doctor Jeff Master's WU blog on July 16, 2007
It's not just the SSTs that are important for hurricanes, it's also the total amount of heat in the ocean to a depth of about 150 meters. Hurricanes stir up water from down deep due to their high winds, so a shallow layer of warm water isn't as beneficial to a hurricane as a deep one. The Tropical Cyclone Heat Potential (above graphic) is a measure of this total heat content. A high TCHP over 80 is very beneficial to rapid intensification. There is less heat energy available this year than in 2005, which recorded the highest SSTs and TCHP ever measured in the tropical Atlantic. However, this is not true in the Western Caribbean, where we have very high TCHP this year. The African dust storms have not penetrated all the way to the Western Caribbean, and SSTs and TCHP have stayed above average. In the unlikely event we get an intense hurricane in late July, it would probably be in the Western Caribbean.


IMPROVING THE INITIALIZATION OF HURRICANE-OCEAN MODELS - as related to TCHP, is a technical, but interesting read about how the GFDL is being used to improve hurricane intensity prediction in the GOM.


LOOP.gif picture by moonlightcowboy

GOM LOOP CURRENT -- The clockwise flow that extends northward into the Gulf of Mexico and joins the Yucatan Current and the Florida Current is known as the Loop Current. The Loop Current is variable in position. At one extreme, it has an almost direct path to the Florida Current, causing the shear in the flow to set up a quasi-permanent clockwise recirculation known as the Cuban Vortex. This feature may help initiate Loop Current expansion.

At the other extreme, the Loop Current intrudes into the Gulf of Mexico, forming an intense clockwise flow as far north as 29.1N. Occasionally this loop will reach as high as the Mississippi river delta or the Florida continental shelf. The Loop Current returns to its direct configuration by slowly pinching off its extension to form a large, warm-core ring that then propagates westward at speeds of 2-5 km day.

The Loop Current draws its waters from the Yucatan Current, which is ultimately fed by the Caribbean Current, Guiana Current and North Equatorial Current. Frequencies of ring separation vary and the annual fluctuations in Loop Current flow are apparently due to wind forcing.

Missing

The above figure shows a series of vertical slices of water temperature in the Gulf of Mexico. This sequence is oriented SE to NW so as to capture the warm eddy's "core" structure. (THAT'S LIKE 92 DEGREES!!!) The temperature data used for this analysis was obtained from bathythermographs deployed from NOAA's WP-3D aircraft on 8/3/99. The domain shown extends from the surface to a depth of 500 meters, between 23� and 29� North latitude and 85� to 91� West longitude.

RAPID INTENSIFICATION

The intensification of tropical cyclones involves a combination of different favorable atmospheric conditions such as atmospheric trough interactions and vertical shear, which lead to good outflow conditions aloft. As a result of this, inflow conditions in the near-surface layer are enhanced. Clearly, as this process continues over the scale of the storm, the upper ocean provides the heat to the atmospheric boundary layer and the deepening process. In this scenario, the upper ocean thermal structure has been thought to be a parameter that only played a marginal role in tropical cyclone intensification. However, after a series of events where the sudden intensification of tropical cyclones occurred when their path passed over oceanic warm features, it is now being speculated that it could be otherwise.

While the investigation of the role of these rings and eddies is a topic of research in a very early stage, preliminary results have shown their importance in the intensification of hurricane Opal (Shay et al, 2000). Therefore, the monitoring of the upper ocean thermal structure has become a key element in the study of hurricane-ocean interaction with respect to the prediction of sudden tropical cyclone intensification. These warm features, mainly anticyclonic rings and eddies shed by the Loop Current, are characterized by a deepening of several tens of meters of the isotherms towards their centers and with different temperature and salinity structure than the surrounding waters.

http://www.aoml.noaa.gov/phod/trinanes/HHP/images/HHPOMB.jpg
(1) OPAL (2) MITCH (3) BRET

These storms passed over areas with very high values of TCHP


(1) Hurricane Opal in the Gulf of Mexico, August-September 1995 (left):
This TC intensified from hurricane-1 (74-95 mph winds) to hurricane 4 (131-155 mph winds) while traveling over a number of warm features in the Gulf of Mexico. In particular, this TC suddenly intensified from hurricane-2 (96-110 mph winds) to hurricane-4 in a period of 10 hours when its track went over a very well defined ring with a mean radius of 150 km that had been shed by the Loop Current. Altimeter-derived fields indicate that the increase in TCHP associated with this warm ring was approximately 30 kJ/cm2. The most striking information of the ocean conditions during the life span of this hurricane over the Gulf of Mexico was that this warm ring was not detected using the AVHRR-derived sea surface temperature fields.

(2) Hurricane Mitch in the Caribbean Sea, October 1998 (center):
This cyclone intensified from hurricane 2 to hurricane 5 (winds above 155 mph) when its track traveled over a region of warm surface waters, experiencing an intensification from hurricane 3 (111-130 mph winds) to 5 with an increase in values of TCHP approximately 80 kJ/cm2 under the track of the TC in 22 hours.

(3) Hurricane Bret in the Gulf of Mexico, August 1999 (right):
This hurricane intensified several times in the SW Gulf of Mexico in a period of approximately 36 hours while traveling over two warm features remnants of one warm ring that had been shed by the Loop Current several months earlier. The increase in TCHP under the track of the TC during this period was approximately 80 kJ/cm2.

In these cases an association was observed between the increase in TC intensity and a raise in the value of TCHP under the track of each of the TCs. Preliminary evaluation of the upper ocean thermal conditions during the intensification of 32 of the 36 strongest TCs in the tropical Atlantic from 1993 to 2000 indicates that their intensification can be associated with the passage of their tracks over regions, with increased TCHP of at least 20 kJ/cm2.
(image and comparison-credit NOAH)

Missing
LATEST STEERING CURRENTS

24hr shear tendency

If you look at the graphic below, you'll see that a number of storms develop this time of year in the area just east of the southern islands. That's where the last few invests (except for 98) have tried to get their acts together and I think that's where we'll also see 90L develop from, if it doesn't develop in the Caribbean first.

The chance (percentage) of a named tropical cyclone in August

Tropical Cyclone Probabilities - Named Storms in August
This is the chance at any particular location that a tropical storm or hurricane will affect the area sometime during August. Based on years 1944 to 1999 in the analysis and counted hits when a storm or hurricane was within about 100 miles (165 km). (Figure by Todd Kimberlain.)


Latest TWO
Latest NHC Tropical Weather Discussion
Look here on the Latest Surface Map for the Itcz location, waves, and other surface features.


"IMHO Tropical Summary"

The African wave, now declared 90L is located at around 11n, 20w in the eAtl with winds of 30 mph. Convection seems to building and is looking more circular in appearance. T'storms still have to persist, become more frequent and more intense for more development. It's the most impressive wave off the African coast this year; yet, it still has some things to prove. Surface pressure is at 1006 mb. If that lowers it will help increase convergence. It also now seems to have some rotation and may be developing a low level center.

Most of the models are in agreement for development. And while there is congruency, it's still early to predict actual tropical formation, a specific track, or landfall! Some of them models are in agreement to a northern Antilles track, but that's a long way out, still. The only land it's close to right now is Africa! There will also likely be several track shifts with the models because the wave is so far out. Even with development, any landfall would be a week or more out.

It'll be interesting to see how much convection it builds early with the increased activity in the Itcz and how quickly it's able to get to TD status. There's still some loitering dry air in the cAtl, but not enough to prevent development. Still, I don't think we'll see any real strengthening until it reaches the area between 45w-55w (see the above chart regarding "August named storms). And, that's only if it can hold everything together along the way. Some dry air and upper level shear could be prohibiting factors as it travels westwards at 15-20 mph. We'll know more in the coming hours with current winds reported at 30 mph, it may be on it's way to becoming a TD later this evening.

The Bermuda/Azores high is ridging far enough south that it will keep this wave's convection clinging to the Itcz. That also means that it keeps more of a westward track until it reaches the region of the southern islands. And, a few of the long range forecasts have it moving more towards the southern islands. That's where things will become more serious. There are several warm currents running through the se Caribbean and if a developing storm finds this area, it will quickly find hot waters for fueling intensification. Any track into the nw Caribbean and the GOM almost means "major" hurricane status and will be a serious threat to the northern Caribbean islands, CA, Mexico and the GOM states.

Plus, there is another African wave about ready to take a dip in the Atlantic. And, it's still possible that we could see some Caribbean and other development, too. One thing's for sure, it's getting more active and conditions appear to be overall much better for development.

It's still early and many things can happen. However, it's not too early to be watching and getting a good hurricane plan! Awareness, preparedness and safety is the name of the game. If you don't have a plan get one. Have a Plan B. Visit Patrap's Blog. He's got some "hot tips" about awareness, preparedness and safety! Get things in order before a storm is bearing down on your location. Don't wait! The tropics are definitely heating up! We may get lucky, but the odds aren't stacked that way. This African wave may just be the "Dean" of storms!

"Hold down the fort and keep the gates closed!"


MLCgoodnight4.gif

Your comments and suggestions are welcome. Thanks in advance!
Have a good one!

MLC


PS: Don't forget to check out Tropical Lagniappe for some great links to other blogs and websites from fellow WU members! There's some great info here and I always learn something each time I visit them!


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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

MLC,

Good work again, pulling together relevant graphics and text with an integrated focus, under an eye-catching title.

One thought I have is that you could truncate the above blog somewhere about:
--------------------------
(image and comparison-credit NOAH)


Latest TWO
--------------------------

...and leaving the "real time" links, I see it having value as a "Tabasco/Hot Gulf" blog which could be "recycled" like Tropical Lagniappe or Patrap's preparedness blog.

[edit] when I look back at whole blog after entering comment, I would leave the "steering current" link in at end if doing blog for recycling purposes.... ie: Hot gulf/ intensification history/ current steering.


Thanks & keep up the good work.

CRS
CRS, why did you just come out and say it was too "dayum" long? lol. Seriously, thanks, good points and I have truncated the blog, nearly to your rec.
Appreciate your suggestions. Maybe, it'll be easier to stroll through. Thanks.
exacto el golfo de mxico es puro combustible listo para incendiarse!!! the Real hurricane season its just about starting in 2 weeks!!!
Buenos dias e mucho gracias, Fabrizzio! el gulfo de mexico es muy caliante!!! (poor espanol,lol)
I'll have a Budweiser and a Dozen oysters on da HAlf-shell ,with a lil Bottle of that there Tabasco too.
That sure is a fine order, Patrap. Could use a dozen myself. lol
Hey MLC

Thanks, for the good read there, super SSTs in the GOM...
I would pray a Storm, doesn't get into the GOM, with those SSTs(Providing conditions are right)...
Thanks for the comments about my blog MLC! I really like yours also! Forget Tabasco.. It's Texas Pete HOT!

Well now the GFS 12z run puts the CV wave into the GOM ryang..

See my Blog for more about it
Link
Thanks, ryang and wsp! I sure hope the GFS is wrong. The GOM is like rocket fuel for these things-highly combustible!!!
Informative, educational and entertaining, nice work cowboy!
Hey, LowCal, man, where've you been? Thanks for the post! Hope all is good with you!

...lol, may be time to pull the ole' "smell factor" theory out, heh? lol
That would be informative, educational and entertaining too cowboy. ;^)
Way to go MLC!!!!

This is a GREAT blog, man. Thanks for your efforts and contributions to WU.

I will make it a point to include you in my daily blog rounds.

Justin
Thanks, Seminolesfan! Things are ramping up, and the potential for a land-falling serious stomr is a little scary.

I appreciate your comments. This has to be about "awareness, preparedness and safety!"
16. LLJ
Smokin!......the Tabasco Blog! LOL


Don't know if you have this link but it's a good one for Africa and the EATL. Only updates every three hours....but it beats six!

Link

Just click on Satellite imagery.
Enjoy.
Thanks, LLJ and got it, appreciate the link. Yeah, it's sharp!
LOVE TABASCO SAUCE...
MLC,
Always stop by here to get the info. Great post. Great analysis and forsight.
Just one tiny problem with todays post.......Still say if you added a little vodka, salt, pepper and Clamato with a stick of celery......Party time :):):) lol
Thx again for the post.

PS...I'm not going to try to spell Whorecheeseestter Sauce:)
Agreed, NP! Party time! lol:D

Thanks for stopping by and comments!
Thanks, all for visiting and the nice comments! Took a little time out tonight and socialized, great food, drink and company, too!

Looks like the days ahead are going to be hooked up! Hope all have a good night's rest. I know this place is gonna get busy!
Thanks for visiting my blog and for you kind words. I agree wisdom may come with age, yet I have known some very wise young people as well...
yes, i allways knew, MLC rocks, thats weather at its best, thanks for the info, i allready got gastritis, from to much heat, so no more tabasco for me.