ATL: TROPICAL DEPRESSION BONNIE - DISCUSSION

[cycloneye]

Just NNW of the little island of Culebra.For those that dont know where Culebra is, you can see it between ST Thomas and Puerto Rico.

[wxman57]

WAY too early to hunt for an LLC with this system. There are plenty of surface obs in the region, and none indicates any turning. Surface pressures are in the 1014-1017mb range across the disturbance, too. With wind shear in the 20-30 kt range, we'll have to wait 2-3 days for it to organize.

I do like those NHC preliminary tracks you can see in the model guidance. Maybe passing south of Key West, though. Final landfall may be close to an Ivanhater on Sunday. But then, I'm estimating development chances at 30-40% beyond 48 hours (about 5% before 48hrs). So still a better chance it's just a tropical wave than a TS or H.

[tolakram]

Loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=20

Notice the flow south and east of PR.



Bands are setting up, however overall flow is to the north, towards the convection. This *might* be the beginnings of a LLC setting up, impossible for me to tell, but if you look at the loop, sped up, you can see what I mean.

[Ivanhater]

WAY too early to hunt for an LLC with this system. There are plenty of surface obs in the region, and none indicates any turning. Surface pressures are in the 1014-1017mb range across the disturbance, too. With wind shear in the 20-30 kt range, we'll have to wait 2-3 days for it to organize.

I do like those NHC preliminary tracks you can see in the model guidance. Maybe passing south of Key West, though. Final landfall may be close to an Ivanhater on Sunday. But then, I'm estimating development chances at 30-40% beyond 48 hours (about 5% before 48hrs). So still a better chance it's just a tropical wave than a TS or H.

Interesting! I remember you saying 50 percent yesterday so I like to trend!

[KWT]

So I guess your thinking north of the islands Wxman57.

Worth nothing the ECM builds the upper high again over the next 24hrs and actually really beefs it up by 48hrs, I just can't see it gaining nearly as much latitude as that NHC track, probably WNW for the next 12-24hrs followed by a bend close to due west would be my call right now personally speaking...IF it stays north of the islands this probably develops before the Gulf IMO.

tolakram, yeah thats what I was thinking, maybe Wxman57 will disagree with me but I don't think surface obs always tell a great story, I see countless times surface obs suggesting there is nothing and recon ends up finding a tiny center...BUT in this case I suspect if there was any LLC its close enough to PR to know pretty quickly. For now all I see is a good circulation at the mid levels.

[Vortmax1]

I can only assume that is a long range radar. If so it is shooting way above whatever might be any kind of surface formation.
There's nothing at the surface out there right now that can be verified.

[wxman57]

Loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=20

Notice the flow south and east of PR.

http://img836.imageshack.us/img836/8384/ztemp.gif

Bands are setting up, however overall flow is to the north, towards the convection. This *might* be the beginnings of a LLC setting up, impossible for me to tell, but if you look at the loop, sped up, you can see what I mean.

I'm seeing surface observations in that area from the East to East-Southeast, so no evidence of any westerly component at the surface yet.

[poof121]

I would assume this light WSW wind on the NE coast of PR is local effects, but correct me if I'm wrong:

http://www.ndbc.noaa.gov/station_page.php?station=frdp4

[Ikester]

From Houston:

OF NOTE...EURO WANTS TO BRING AN EASTERLY WAVE TO THE
TEXAS COAST BY SATURDAY WHILE GFS HOLDS OFF ON THIS IDEA UNTIL MON
OR TUE. IT APPEARS ENSEMBLE IS TILTING TOWARDS A MORE TRADITIONAL
LATE JULY PATTERN...WEAKER (FLATTENED) SOUTHERN PLAINS RIDGING...
INCREASED PROBABILITY OF THE HIGHER FREQUENCY OF EASTERN TROPICAL
WAVES/HIGHLY MOIST AIR MASSES HEADING INTO THE WESTERN GULF. 31

[wxman57]

WAY too early to hunt for an LLC with this system. There are plenty of surface obs in the region, and none indicates any turning. Surface pressures are in the 1014-1017mb range across the disturbance, too. With wind shear in the 20-30 kt range, we'll have to wait 2-3 days for it to organize.

I do like those NHC preliminary tracks you can see in the model guidance. Maybe passing south of Key West, though. Final landfall may be close to an Ivanhater on Sunday. But then, I'm estimating development chances at 30-40% beyond 48 hours (about 5% before 48hrs). So still a better chance it's just a tropical wave than a TS or H.

Interesting! I remember you saying 50 percent yesterday so I like to trend!

My coworker suggests it may even turn north before entering the Gulf. Most storms that develop in that region head toward the Carolinas. However, this one may not develop until it gets farther west, closer to the FL Straits.

I think I said 40-50% a few days ago, but that was based on it having a better MLC and possibly an LLC then.

[TCmet]

I hope those in Hispaniola, especially Haiti, are monitoring the progress of 97L very closely because IMHO even if it doesn’t develop into a TD, the potential for flooding certainly exists.

I'm here in Haiti on a consulting mission with the UN, and I will assure you that the Government of Haiti is taking the threat from 97L very seriously. This morning, the country was placed on Yellow alert to prepare:
http://www.meteo-haiti.gouv.ht/vigilance.php

But what to actually DO with that information to prepare the 1.2M people still living in camps is the big question......

[Ivanhater]

WAY too early to hunt for an LLC with this system. There are plenty of surface obs in the region, and none indicates any turning. Surface pressures are in the 1014-1017mb range across the disturbance, too. With wind shear in the 20-30 kt range, we'll have to wait 2-3 days for it to organize.

I do like those NHC preliminary tracks you can see in the model guidance. Maybe passing south of Key West, though. Final landfall may be close to an Ivanhater on Sunday. But then, I'm estimating development chances at 30-40% beyond 48 hours (about 5% before 48hrs). So still a better chance it's just a tropical wave than a TS or H.

Interesting! I remember you saying 50 percent yesterday so I like to trend!

My coworker suggests it may even turn north before entering the Gulf. Most storms that develop in that region head toward the Carolinas. However, this one may not develop until it gets farther west, closer to the FL Straits.

I think I said 40-50% a few days ago, but that was based on it having a better MLC and possibly an LLC then.

Ahh fair enough. I noticed the GFS Para was showing that same scenario your coworker is talking about last night.

[Ivanhater]

[tolakram]

Shear appears to be rapidly declining.

[KWT]

My coworker suggests it may even turn north before entering the Gulf. Most storms that develop in that region head toward the Carolinas. However, this one may not develop until it gets farther west, closer to the FL Straits.

Unless TC can suddenly punch through large upper highs...that isn't going to happen. Looking at the current set-up I see WNW for the next 12-14hrs, then a bend to the west as the upper high strengthens. I just thought I'd add every single TC in the last 45 days as been west of track globally...just a little interesting tibbit for people!

I like the AL/MS area myself right now personally speaking...may just stay north of most of the islands but depends on where exactly the LLC forms.

[Aric Dunn]

It looks as though a small MCS maybe developing north of PR on radar.. could be some very early indications of more organization... no LLC for awhile but if the complex persists and works down to the surface we may see something in a day or so....

[Gustywind]

LATEST

[Vortmax1]

But what to actually DO with that information to prepare the 1.2M people still living in camps is the big question......


Thank you TCmet!
I need to translate your link.
It's nice to know people like you are there to help.

[Ivanhater]

[KWT]

Without a doubt there is a MLC with that convection, the radar looks quite obvious in that regards.