Tropical Tidbits from the Tundra

Dean update August 18th

By: Levi32, 2:36 PM GMT on August 18, 2007

**Update 12:30pm Eastern**

The NHC 11am forecast track did not change much, and Dean continues on a heading of about 290 towards Jamaica. This update is to say that Dean is finally entering his EWRC that I predicted last night. The eye is contracting now down to 11 miles wide, and the wall is open to the south. A new outer eye-wall is evident on visible imagery(image below). This will temporarily weaken Dean until the cycle is over, when he will restrengthen prior to hitting Jamaica. The main things to watch during this cycle are how weak Dean gets, and how big his wind field gets. EWRCs are known to greatly help a hurricane expand its wind field, which Dean is expected to do as he grows larger. I will update again this evening or sooner if conditions warrant.



Saturday Morning:

After a very impressive period of rapid strengthening to a strong Cat 4 hurricane last night, Dean seems to have leveled off for the time being. Dean's eye continues to slowly contract and is now down to 12 miles wide. Eventually Dean will have to go through a major EWRC to expand his wind field and "replace" the eye. The CDO is slightly asymmetric with most of the deep convection on the east side of the eye. This may be due to a little bit of dry air that got entrained into the west side, but Dean shouldn't have to worry about that. The potential for Dean's future intensity are through the roof especially in the northwest Caribbean. I fully expect Dean to be a Cat 5 during at least half of his time in the NW Caribbean. His duration and intensity as a Cat 5 will likely be determined solely by EWRCs and land interaction.

The models this morning have finally come to a nicer agreement, with the 6z GFDL coming more in line with what I see as the most likely track across the NE Yucatan Peninsula and then hitting extreme southern Texas. Once again the key is the behavior of the ULL currently moving over southern Florida. The GFDL is more inclined to have Dean follow the SE flow aloft that will be setting up to his west. The GFS stubbornly builds the ridge just barely enough to keep Dean from entering that flow on the west side of the ridge. It's nearly impossible to tell which models are right at this point, we just need to watch them and the ULL and try to make sense of it all. I still have great concern that the earlier GFDL runs may be correct, but right now the consensus of the models looks about right, and is in great agreement with the NHC track. Dean has assumed a more NW course at about 295 over the last 6 hours. This may only be a jog compensating for last night's westward jog, but if this motion continues into this afternoon it will be a cause for concern. I still believe that if Dean makes it directly between Jamaica and Cuba then Texas will have a big owie coming through the Yucatan Channel. If Dean moves over or south of Jamaica than most of the models will be correct on a pass over the Yucatan and into northern Mexico. In my mind this will be the turning point in Dean's track, but we have a long way to go and no single 12-hour period is going to spell the end-game with this storm. We have to take it one hour at a time, one day at a time.

We shall see what happens!
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Updated: 4:32 PM GMT on August 18, 2007

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Hurricane Dean

By: Levi32, 3:23 PM GMT on August 17, 2007

Friday Morning:

Dean has re-organized a bit overnight and is now strengthening again. Latest vortex message reported a closed eyewall and a central pressure of 964mb. Martinique was the island worst hit by Dean, but never got into the eyewall. The highest reported winds were 66 knots gusting to 75. Dean is now moving on, and Jamaica is next in line to be hit. This is a bad situation for them, and it is very likely that they will get a direct hit from a large Cat 4 hurricane. The current environment is very conducive for strengthening, and will only get better as Dean moves into the NW Caribbean. By the time Dean reaches this area he will be an extremely large and powerful hurricane, possibly Cat 5.

After the NOAA plane put yesterday's flight data into the 0z model runs, the consensus has shifted slightly north, and many more models take Dean through the Yucatan Channel. The NHC track at 11am is also shifted north, and has Dean crossing the NE tip of the Yucatan Peninsula. Regardless of whether Dean encounters Mexico or not, the consensus of the models continues to point Dean towards Texas. The fine yet extremely important details of this track will be determined by an upper-level low situated over the western Bahamas. This low was forecasted by the GFS and other models to move west ahead of Dean, allowing the high to build and steer Dean west into Mexico. However, this ULL has yet to start moving west, and Dean is catching up. If Dean can make it close enough to the ULL before it takes off westward, then Dean will be able to move through the weakness in the Bermuda High left behind by the ULL, and Dean will most likely move through the Yucatan Channel. This would be the worst-case scenario as Dean would not be weakened by moving over the Yucatan, and conditions in the GOM would support a major hurricane all the way to the coast. Now this isn't a time to get panicky yet, as a lot could still change. As I have said the past 3 days the models usually don't hold the same track for an entire week straight, and we will see some more shifting around before the models finally settle down. We have plenty of time to watch Dean, but right now people in Jamaica need to take this one seriously.

We shall see what happens!
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Dean update Thursday, August 16

By: Levi32, 3:14 PM GMT on August 16, 2007

Thursday Morning:

Dean has continued to strengthen and is now the first hurricane of the 2007 season. A small eye has developed, and can be seen on visible satellite. This feature has started to become obscured but this is probably only temporary while Dean organizes. Dean is continuing to struggle a bit with some dry air to the NW being sucked into the circulation, but convective banding is starting to wrap around that side and the dry air's affect on Dean should be greatly lessened once he gets into the Caribbean. Hopefully this dry air will keep Dean at bay long enough to spare the islands a strong Cat 2, but I still think they will see 100+mph winds. Wind shear is fairly light (5-10 knots) and there is very little to inhibit Dean's intensification into a major hurricane during the next few days.

The track is the most debated issue with this storm. After hopping around for several days, the models have finally come to some sort of agreement on taking Dean due west and slamming him into the Yucatan. Personally, I'm not ready to buy this just yet. For one thing it is rare for the GFS of all things to be NOT recurving a storm lol. The GFS always has had problems with transferring heat from the tropics to the mid-latitudes, and it is very suspicious that it would be showing this solution. The GFDL, which runs on GFS input, had been following along with the other models until the 6z run this morning, when it caught us all by surprise. The GFDL now takes Dean across the western tip of Cuba and into the central GOM as a Cat 4, heading towards (can you guess?) Louisiana. Now this is only one run, and I would like to see some consistency with this solution before hyping it up, but it is interesting again to see the GFDL differ so much from the GFS when they are essentially the same thing with the GFDL just having higher resolution and special tropical enhancements. Also it is looking like most of the global models are having problems picking out the hemispheric upper-air pattern. This may be one of the reasons why the models were hopping all over the place with every run a few days ago. They may have settled with one solution for now, but there is a lot of time for that to change, and as I know all of you know, the models rarely stick with the same solution for an entire week, so we have time to change. Recon planes at high altitude will get gathering data on the upper-air conditions around Dean today, which will hopefully help the models sort all this out.

Right now, our concern should be directed at our neighbors in the Antilles Islands, which will be feeling the brunt of Dean's wrath probably as a Cat 2 hurricane. The island I expect Dean's eye to pass over is Martinique (France), and obviously the surrounding islands will get a bashing as well. Next up is Jamaica, which sadly to say may get the beating of a major hurricane in 3-4 days. By that time Dean will not be just stronger but also much bigger. The storm is already re-organizing and enlarging itself, and we could be looking at a monster in the NW Caribbean once it gets there. An air-force recon plane will be investigating Dean later today.

Tropical Storm Erin has made landfall in SE Texas as a moderate TS with 40-knot winds. There were high expectations for intensification with this storm, but for some reason Erin just never really pulled it together. The main threat with this storm will be the rainfall, and decent amounts have already fallen across the area.

We shall see what happens!
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Updated: 3:26 PM GMT on August 16, 2007

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TS Dean and Invest 91L

By: Levi32, 4:12 PM GMT on August 14, 2007

Tuesday Morning:

TD 4 has finally strengthened into TS Dean this morning. The upgrade was prompted by a slight increase in organization from last night and a small CDO over the center. However most of the convection remains in the SW quadrant of the storm and easterly shear will continue to bombard it for a couple of days. After that slow steady strengthening should begin, and Dean should be a hurricane before reaching the Antilles Islands. Track is by far the most pressing issue with this storm, and it is far from certain. The GFS, after driving Dean into Mexico with several runs in a row, has now come back north bringing Dean north of or over Puerto Rico and Hispaniola and threatening the SE coast of the US. Most of the models have shifted to the right with the last couple runs, forecasting a weaker Atlantic ridge. The strength of this ridge and the penetration of a trough forecasted to come off the east coast in a few days will be crucial to the future path of Dean. Anywhere from Brownsville to Hatteras and all surrounding areas could be at risk. Another key will be if Dean get severely weakened by moving over the big Caribbean islands. An undisturbed Dean will probably be a major hurricane moving towards the coast, but we could be dealing with only a Cat 1-2 if Hispaniola or Cuba rip it up a bit. Bottom line this needs to be watched by all interests in the western Atlantic Ocean and we have plenty of time to speculate. Residents in the Antilles Islands should be preparing for a Cat 1-3 hurricane in 3-4 days.

Turning our attention closer to home, we will probably have TD 5 form out of Invest 91L in the southern GOM this afternoon. The disturbance now has a nicely defined surface circulation evident on visible imagery. All the convection is currently NE of the center, partially due to the fact that the center is very close to the Yucatan. Models are currently bringing this system close to the Texas/Mexico border, and interests in that area should prepare for heavy rains and TS winds with this. I don't expect this system to have time to wind up before it makes landfall. Given 3-4 days this thing could be a serious hurricane, but it only has 48 hours at most over water and I expect the worst this will become is a 50-knot TS. This will be a large storm, heavy on the east side, and the main threat will be very heavy rains and flooding in its path. Interests in the western Gulf of Mexico should keep a watchful eye on this over the next couple days.

We shall see what happens!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 000
ABNT20 KNHC 141517 CCA
TWOAT

TROPICAL WEATHER OUTLOOK...CORRECTED
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1130 AM EDT TUE AUG 14 2007

...CORRECTED FOR DAY...

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON RECENTLY
UPGRADED TROPICAL STORM DEAN...LOCATED ABOUT 1490 MILES EAST OF THE
LESSER ANTILLES.

SATELLITE IMAGES AND SURFACE DATA INDICATE THAT THE AREA OF LOW
PRESSURE IN THE SOUTH CENTRAL GULF OF MEXICO IS GRADUALLY BECOMING
BETTER ORGANIZED AND A TROPICAL DEPRESSION COULD BE FORMING. A
RECONNAISSANCE AIRCRAFT IS SCHEDULED TO CHECK THE AREA THIS
AFTERNOON. THIS SYSTEM IS EXPECTED TO MOVE TOWARD THE
WEST-NORTHWEST OR NORTHWEST AT 10 TO 15 MPH. ALL INTERESTS IN THE
NORTHWESTERN GULF OF MEXICO...INCLUDING THE SOUTHERN TEXAS AND
NORTHEASTERN MEXICO COASTAL AREAS...SHOULD CLOSELY MONITOR THE
PROGRESS OF THIS SYSTEM...AND BE READY TO TAKE ACTIONS. TROPICAL
STORM WATCHES OR WARNINGS COULD BE PROMPTLY REQUIRED FOR A PORTION
OF THE COAST.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER AVILA
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Tropical Storm Dean:



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Invest 91L:



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90L: Dean in the making?

By: Levi32, 10:36 PM GMT on August 11, 2007

Saturday Afternoon:

We are just a week away from the start of the peak of hurricane season, and after an extremely quiet beginning, some action has finally come our way. A vibrant tropical wave that came off the African coastline last night has already been designated Invest 90L, and it's not even past the Cape Verde Islands yet. As usual the wave needs a little time to adjust to the oceanic environment and convective processes, but unlike nearly every wave before it, it has held its convection over water for over 12 hours. The latest QuikScat pass over the area shows a remarkably well-defined surface circulation already in place. Convection remains disorganized at this time, but steady organization should soon ensue as shear weakens and SSTs become warmer as 90L moves west. This storm could be the real deal folks. Every global model has been jumping all over this wave with every single run since it was still in the Indian Ocean. Climatology is in favor of African waves to start developing, and the negative MJO pulse is now gone, which greatly increases the chances of development anywhere in the Atlantic. I believe this could be TD #4 by tomorrow, and TS Dean as early as Monday. Looking onward I think we will see our first hurricane and possibly our first major down the road.

As for the potential track of this developing storm, that's really difficult to say. The GFS has had this thing hitting everywhere from Texas to New Foundland. My opinion is that the hemispheric pattern is such that this will not recurve, and will make it to US longitude before making a move northward. But lets not jump the gun yet. If this develops it could hit anywhere from the Caribbean to Cape Hatteras, and any encounter with land is at least 4 days away. We have tons of time to watch this thing and see where it might go. Lets have some fun while it's still over water LOL. I have a feeling this could be our first big storm of the year to observe.

A second area of interest which is being rapidly forgotten in all the screaming about 90L is the western Caribbean, which is absolutely boiling over with moisture. The easterly trades have all but stopped over the western Caribbean and GOM thanks to the North American pattern that is in place. This is resulting in a piling up of air and energy, and a bunch of tropical waves running into each other east of the Yucatan. It's scary how much energy is available in this area is something develops. Conditions are plenty favorable for anything to pop up at any time, and a rabbit out of the hat will intensify RAPIDLY if it develops a surface circulation and stays over water. Right now all models have dropped any development forecasted in this area, with the exception of the WRF, which always hypes these sorts of things anyway just like its big brother the CMC. Bottom line, watch this very closely through early next week, as there is lots of potential for some development in this area early next week.

We shall see what happens!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 000
ABNT20 KNHC 112114
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
530 PM EDT SAT AUG 11 2007

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

A BROAD AREA OF LOW PRESSURE OVER THE WESTERN CARIBBEAN SEA IS
PRODUCING DISORGANIZED SHOWERS AND THUNDERSTORMS NEAR JAMAICA...THE
CAYMAN ISLANDS...AND CUBA. DEVELOPMENT OF THIS SYSTEM...IF
ANY...IS EXPECTED TO BE SLOW TO OCCUR AT IT MOVES WESTWARD INTO THE
YUCATAN PENINSULA AT ABOUT 10 MPH.

A VIGOROUS TROPICAL WAVE...LOCATED OVER THE FAR EASTERN ATLANTIC
OCEAN JUST WEST OF THE COAST OF AFRICA...IS PRODUCING DISORGANIZED
SHOWERS AND THUNDERSTORMS. CONDITIONS APPEAR FAVORABLE FOR GRADUAL
DEVELOPMENT OF THIS SYSTEM AND A TROPICAL DEPRESSION COULD FORM
DURING THE NEXT COUPLE OF DAYS AS IT MOVES WESTWARD AT 15 TO 20
MPH.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER RHOME
LATER TODAY IF NECESSARY.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



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99L still alive, GOM disturbance a possible threat.

By: Levi32, 2:25 PM GMT on August 02, 2007

Thursday Morning:

Invest 99L has for the most part remained worthy of its name over the last 12 hours. This thing has now sustained deep convection for more than 30 hours, and no matter how disorganized it was yesterday, that is a huge accomplishment. Now, what can it do with this new-found energy? Not much at the moment. For starters there is no low anymore and 99L is just an open wave again per the last several QuikScat passes in a row. The latest pass clearly shows the wave axis position which is nice. Deep convection has really gone off over the last 6 hours, mostly west of the wave axis, but is now shifting to the east side due to southwesterly shear being impinged upon 99L by an upper-level low in the western Caribbean. I'm noticing something interesting about this shear. Remember yesterday it was from the east, pushing all the convection west of the center. Well this morning, thanks to the ULL in the western Caribbean, the shear has switched and is now blowing from the SW, which is more classic and "normal" for a developing system. I think this may have a great deal to do with the blow-up, despite the fact that it's trying to erode the SW side. I know someone is going to have a problem with this lol, but my take on it is when the shear was easterly, there was no convection on the east part, so the normal moist inflow channel that comes into a storm in the SE quad via the southerly winds on the east side of the low, was in a way cut-off and couldn't function like it's supposed to and feed the low. This morning the shear is from the opposite direction so there is more convection on the east side. This is allowing all that moisture from the inflow channel to actually feed the wave better. Before there was no intake directly into the convection, because there were northerly/northeasterly winds where the convection was. Now it's more normal-looking and the convection is moving back to the SE and NE quads.

Sorry I kinda slipped there into my rambling on and on mode. Please bare with me I'm really tired this morning. Anyway, there is another recon en-route to the system right now, and it will be very interesting to see what they find. They bumped the flight up 4 hours from the previously scheduled 12z to 16z, and I'm greatful because the system is much more worth observing now than it was 4 hours ago. Part of 99L's problem is how fast it is moving westward. The rapid movement has been inflicting shear on the system, and it needs to slow down before entering the western Caribbean or it may not survive. However, the NHC discussion at 8am eastern said that the forward speed had decreased significantly to 10 knots, so we'll see if that is verified later.

Models still hold the same tracks, maybe nudged north a bit, but it's too early to tell where this might go if it develops. Right now the bottom line is it's heading into the most favorable region for development in terms of SSTs and TCHP. Wind shear will be a problem with that ULL south of Jamaica in the way, but the ULL is moving westward as well, and if 99L really is slowing down then it might just sit behind the ULL until it moves out of the way. We'll see how things go during the diurnal minimum today. A new low is currently trying to form on the SW edge of the deepest convection, so we'll see how that works out. At this point 99L is just a wave, but a very healthy one, and still has a fighting chance to survive. It's still taking baby steps, and will continue to develop slowly.

In other news, the GOM blob hasn't changed much, but the remains of the old front will continue to be a threat to develop in the next few days as the front sits nearly stationary in the northeastern Gulf of Mexico.

We shall see what happens!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...SPECIAL FEATURES...
A 1011 MB LOW PRESSURE CENTER IS NEAR 12N61W...MOVING WEST
10 KT. THIS LOW PRESSURE HAS BEEN WEAKENING LITTLE BY LITTLE
AND HAS BECOME AN OPEN TROPICAL WAVE AT THIS POINT BY
02/0900 UTC. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS FROM
12N TO 15N BETWEEN 62W AND 67W. THERE ARE NO SIGNS OF TROPICAL
CYCLONE FORMATION AT THIS TIME. THE SYSTEM STILL HAS SOME
POTENTIAL TO BECOME A TROPICAL DEPRESSION DURING THE NEXT
DAY OR SO AS IT CONTINUES MOVING WESTWARD NEAR 20 MPH.
A RECONNAISSANCE PLANE WILL INVESTIGATE THE AREA AGAIN
LATER TODAY IF NECESSARY.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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99L makes another comeback

By: Levi32, 3:10 PM GMT on August 01, 2007

Wednesday Morning:

Well, I must say I'm a little baffled by how healthy 99L looks this morning. We must have traveled back in time to Ernesto of last year LOL. Against all odds, 99L has apparently been able to fight off most of the dry air, and over the past 6 hours has sustained a sizable burst of convection. The COC is on the right-hand side of most of the deep convection due to some light easterly shear, and I don't know if it's closed again yet. There have been no more QuikScat passes since last night, so it's really hard to tell how the circulation is doing, but looking at visible imagery this morning, I'd say it is improving. To me it still looks like an open wave, and that is what it was 5 hours ago. Now, 99L may look resurrected now, but as I was saying last night if this thing is going to revamp it needs to hold on through an entire day if it wants to become a TD. Remember Sunday night? It looked like a comeback, but it dissipated in the morning. Convection has lasted about 3 hours later this morning than it did yesterday morning, but it needs to survive the diurnal minimum.

The system will be crossing the Antilles Islands today, where we will get a nice radar view of the system. Models are taking this on a generally WNW track through the Caribbean and into Central America, but its future track is now very much in doubt if it develops today or tomorrow. Now just because it looks nice this morning doensn't mean it's going to bomb out or anything today. This system has already shown itself to be a slow developer, and it needs to hold its convection and reform a tight COC today if it's going to be in contention for TD status. This is definitely something to watch.

Another area of potential interest is a stationary front in the northern Gulf of Mexico. A low is forecast to form along this front, and could undergo some slow development as it just kind of sits there for a few days. Nothing to get hyped about, but all fronts in the GOM need to be watched, as they have a reputation for being nasty creatures.

We shall see what happens!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 000
ABNT20 KNHC 011510
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1130 AM EDT WED AUG 1 2007

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE AREA OF LOW PRESSURE ASSOCIATED WITH A TROPICAL WAVE LOCATED
JUST EAST OF THE WINDWARD ISLANDS HAS BECOME A LITTLE BETTER
ORGANIZED THIS MORNING. AN AIR FORCE RECONNAISSANCE AIRCRAFT IS
SCHEDULED TO INVESTIGATE THIS AREA THIS AFTERNOON. WHILE
ENVIRONMENTAL CONDITIONS DO NOT APPEAR ESPECIALLY FAVORABLE FOR
DEVELOPMENT...THERE IS STILL SOME POTENTIAL FOR THIS SYSTEM TO
BECOME A TROPICAL DEPRESSION DURING THE NEXT DAY OR TWO AS IT MOVES
WESTWARD NEAR 15 TO 20 MPH. REGARDLESS OF WHETHER DEVELOPMENT
OCCURS...THIS SYSTEM WILL LIKELY BRING SQUALLS TO THE WINDWARD
ISLANDS DURING THE NEXT DAY OR SO.

THE LARGE AREA OF CLOUDINESS BETWEEN BERMUDA AND NOVA SCOTIA IS
ASSOCIATED WITH AN EXTRATROPICAL LOW. FORMATION INTO A TROPICAL OR
SUBTROPICAL CYCLONE IS NOT EXPECTED.

A LARGE AREA OF CLOUDINESS AND SHOWERS HAS DEVELOPED OVER THE
NORTHEASTERN GULF OF MEXICO IN ASSOCIATION WITH AN OLD FRONTAL
ZONE. SOME SLOW DEVELOPMENT OF THIS SYSTEM IS POSSIBLE DURING THE
NEXT DAY OR TWO AS IT REMAINS NEARLY STATIONARY.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER RHOME/BEVEN~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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Antilles Radar Loop

NASA zoomed-in visible loop of 99L

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Updated: 3:24 PM GMT on August 01, 2007

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Levi Cowan has been tracking tropical systems since 2002, and is currently working on his bachelor's degree in physics at UAF.

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