Ed Dunham
Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)
Reged:
Posts: 2565
Loc: Melbourne, FL
|
|
I'll offer a different point of view - maybe even a bit controversial because it will fly in the face of Conventional Wisdom but I think that its really what is happening with TD 9.
Without bantering around the topic, I believe that TD 9 is still alive and well - and its still a TD. At 23/00Z I had the low-level center (yep, I think that its still got one) at 17.0N 68.5W. sometimes will hedge their bet a little by 'projecting' the coordinates a little toward where they believe that the center will be at the time of their next scheduled forecast bulletin. Usually this works out okay since the last intermediate position report can always be adjusted in the next 'full update' forecast. But in a weak system, this approach has a flaw in that a LLCC can be lost if you project ahead and the system unexpectedly slows down. I'm pretty sure thats what happened today with the 15Z bulletin. The recon couldn't find anything because it was directed to examine an area which was too far to the WNW of where the center really was. Here's where I think that TD 9 has been over the past 24 hours:
22/00Z 15.1 66.6
22/03Z 15.4 67.0
22/06Z 15.7 67.4
22/09Z 16.0 67.7
22/12Z 16.3 67.9
22/15Z 16.5 68.1
22/18Z 16.7 68.3
22/21Z 16.9 68.4
23/00Z 17.0 68.5
TD 9 really put on the brakes and is currently drifting northwest at 2 or 3mph. Although I don't pay a great deal of attention to them, I decided to take a look at the models and the really surprised me - so much of a surprise that it looked like an error in the model. The had brought the TD to just about a dead stop and kept it that way for 5 days. Now when a model is having a rough year verification-wise you don't pay much attention to it, but in this case, I wondered why it would project a stationary storm. So I took a look at the current and projected steering currents where the TD is located and guess what - zero - zip - zilch for many days, and I suspect that the had picked up on that.
Examining the entire basin, everything has really slowed down, so the upper air forecast models may be on to something. TD 9 may be around (in roughly the same spot) for quite awhile until some other atmospheric change forces some steering currents into that area - and its not even strong enough to create any detrimental upwelling. Okay - its your turn.
Cheers,
ED
|
HanKFranK
User
Reged:
Posts: 1841
Loc: Graniteville, SC
|
|
well, i just posted on something like this over on the main board.. not really the same conclusion, but ed may have found the piece of the puzzle i was missing. honestly from watching the low cloud motions away from the storm i don't see how there can be any kind of surface low.. but the only way i could tell for sure is if the convection totally goes out.. short of that it's always possible that there's a really awkward center down there.
based on how well the convection is going.. at least some of the dynamics are still there.. so t.d. 9 really can't be called out until they go away. if they did.. it would be disappointing in a way since it would bust my (and everybody else's) ideas, but on the same token it would be for the better.. if this develops it has florida written all over it.
HF 0409z23august
|
|
Previous
Index
Next
Threaded
Edit
Reply
Quote
