Tropical Depression 9 Update

Well while many had written it off, Invest 99L did not listen and by Sunday we had Tropical Depression 9 on our hands just north of eastern Cuba. The Hurricane Center quickly jumped back on the bandwagon and issued basically the forecast track we still have right now. That track would take the system, likely a tropical storm by then, into the Florida coast somewhere near Cedar Key, Florida, right in the crook of Florida. The major models seem to support this scenario, indicating a trough will dip down into the southeast by mid week and turn the system to the northeast. Before we look at my ideas on the storm, here is the most current information based on Hurricane Hunters in the system.

At 1 PM CT Tuesday

Maximum Winds: 30 kt  Gusts: 45 kt
Minimum Central Pressure: 1005 mb
Radius of Circulation: 150 NM
Radius of Maximum Wind: 60 NM
Eye Diameter: N/A

In this animated loop of the visible satellite imagery, you can sort of see where the center is located by the clouds at top-left of the cloud mass curving south into the system. The center is actually located just under the northwest corner of the cloud mass. It has not yet wrapped up completely around the center but is very close to Tropical Storm intensity. It would not surprise me if we see it named later tonight. Now it is not easy to see, but looking closely at the swirling clouds, it appears the system is moving predominately to the west very slowly. Officially, the NHC says the motion is west-northwest at 9 mph. That has a lot to do with my problems with the current forecast track. This system has been consistently running south of where the models said it should go. This time last week it was supposed to impact the central Florida coast. By later in the week, we were told the system would likely impact just south of Miami and into the Florida Keys. Late week, the system was supposed to pass right through the Florida Straits. But each time, it actually traveled farther to the south, actually hugging the Cuban coast until yesterday. So each forecast got shifted south. Fast forward to now and the system is still farther south than Key West.

Let’s take a look at what the models have forecast over the past few days. We are looking at where the models expected the storm center to be at 1 PM today. It shows the projected position and then the time and date the forecast was issued by the NHC.

FORECAST 1PM TODAY            FORECAST ISSUED

  • 25.1N  87.6W                                    4PM SUN
  • 24.7N  87.1W                                    4AM MON
  • 24.6N  86.6W                                   4PM MON
  • 24.2N  87.3W                                   4AM TUE
  • 24.2N  87.4W                                   Actual Location

Do you see it? The position in longitude, or West, has been pretty consistent. But check out the forecast latitude, or North. It has consistently tried to move the system farther north, in a direction of west-northwest or even northwest, But each time the position was reassessed and a new forecast issued, they had to push farther south. Until we reach now and find the system almost a full degree south of where the models forecast it to be. This system has continued to defy the models and run south of projections. Again, I fully agree with the major global models that a trough will dig into the northern Gulf over the next 72 hours or so. If it picks up the system, it would turn from west-northwest, to the northwest, then north, and finally northeast.

First off that is a lot of turning. But the system is relatively small and not moving that fast, so it is very capable of making the turn. But I see two kinks in the current forecast. First off, it is failing to accept the general trend of this system staying farther south than expected. And this trend moves the system quietly farther west over time. That means the turn to the north and northeast takes place further west and also pushes landfall to the west. This is a near certainty unless something happens very quick in the general motion. Second, the farther south the system stays, the later the trough picks it up since it has to wait for the trough to dig that far. We are not yet seeing fronts sweep through and move well into the Gulf. SO how deep will this trough be? I am not sure?

This is the latest animated water vapor loop of the eastern US and Gulf of Mexico. It shows us the major movements of the air masses. If you look near the junction of Florida, Georgia, and the Atlantic Ocean, you will see a swirl in the clouds. That is what should pick up the system and shoot it off to the northeast. But looking at the motion of clouds in the northern Gulf, I do not see it exerting an influence on clouds near the coast, nevertheless well south in the Gulf.

So my gut feeling is that the idea of a landfall near Cedar Key is a long shot right now. I would take the projected path and keep moving it west until we see the storm begun to make a major turn. I currently feel Berwick Bay and Louisiana will dodge the bullet on this one. But if you plan to head for anywhere from Biloxi to Panama City, keep your eyes on this system until it makes that turn. The only threat I could foresee to Louisiana would be if the trough misses the system allowing it to king of meander in the central Gulf looking for direction. Based on the models, I think this is a long shot, say less than 15%, which is about what I also give a landfall on the Peninsula of Florida. My best guess right now would be extreme western Florida, but it is a guess.

As for intensity, I think this is nothing more than a tropical storm. That has its positives and negatives. On the positive side, you have little wind damage and no surge. On the negative side of things, tropical storms are huge rain makers and tornado generators. We do not need either of those things any Louisiana right now! Finally, keep your eyes on the far eastern Atlantic. The models are hinting at a major storm developing over the next week, with none of the inhibiting effects 99L saw. And it is pointed somewhere at the US in the models. We shall see???

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