Area in the Bahamas: Is Invest 98L

[boca]

This looks like an ULL but it’s moving WNW and maybe it might be something the models might latch onto.

[floridasun78]

This looks like an ULL but it’s moving WNW and maybe it might be something the models might latch onto.

unlikely it likely dispear by tonight or saturday

[northjaxpro]

Convection has increased substantially with a mid-upper Low, which is now just east of the Central Bahamas. This area has been moving w/nw the past few days. Convection definitely has flared considerably the past 12-24 hours with this feature. I am beginning to wonder if this feature is trying to work itself gradually to the surface.

A feature to watch, especially as it nears the Central and NW Bahamas and eventually impacts them later today and tonight, and the Florida peninsula potentially mid week.

We are in that time of the year folks. You have to watch these type of features that can work itself down to the surface very closely.. Tropical cyclones can spin up quickly in this area of the basin especially. We all know the past history well...

[northjaxpro]

NHC and WPC indeed shows a rather vigourous surface trough across the Central and into the NW Bahamas

Satellite imagery.looks quite impressive this morning with expanding convection approaching the region. Since the time of my earlier post 4 hours ago, this feature definitely is trying to attain a surface reflection to me. I am awaiting the first visible images to show shortly.

This needs to be watched closely.

[AJC3]

This feature has always had a reflection at 850MB. Its origin is not a tropical wave, but a piece of vorticity that fractured off of a decaying frontal zone over the central Atlantic between 30-35N, then moved SW-WSW for the past 5-6 days. It just happened to move underneath an upper level trough as it got north of the GA and approached the Bahamas

If you want to go back and look through the AFDs from WFO MLB, you'll see several references to it. I think it was first mentioned last Wednesday. You'll also see several references to it in the TWDATs from NHC since late last week. Deffo not a true tropical wave, but rather a "pseudo-Twave" of sorts.

Better yet...

Area Forecast Discussion
National Weather Service Melbourne FL
415 AM EDT Wed Aug 14 2019

.DISCUSSION...

<snip>

Early-mid next week (Sunday-Wednesday)...Strong late summer ridging is forecast to continue building over the central/mid-Atlantic into the NE CONUS. This will back the mean layer flow from southerly to SE-E, and be accompanied by additional mean layer drying early next week. While this type of flow pattern favors the western peninsula for highest diurnal precip coverage, a potential fly in the ointment is the possibility of an inverted trough moving underneath the ridge across the Bahamas and into Florida by next Tue-Wed as advertised by the 00Z ECM. Rather than an AEW, this trough appears to originate from vorticity fracturing off an old frontal boundary over the central Atlantic, although it would essentially have the same impact as a T-wave should the ECM eventually verify. Would prefer to see this sort of solution maintain itself and pick up some support from the GFS suite before indicating any sort of increase in POPs. Will therefore maintain a climo-based onshore flow regime forecast of mid range scattered (30-40 coast/40-50 inland) with near normal maxes and above normal mins.

$$

[northjaxpro]

This feature has always had a reflection at 850MB. Its origin in not a tropical wave, but a piece of vorticity that fractured off of a decaying frontal zone over the central Atlantic between 30-35N, then moved SW-WSW for the past 5-6 days. If you want to go back and look through the AFDs from WFO MLB, I think you'll see several references to it. I think it was first mentioned last Wednesday.

OK. Thanks. I will. I have been distracted the action around here these past several days with the persistent trough over the N GOM and North FL.

Visible imagery looks to me like rotation/spin is trying to get going just east of Eleuthera Island.

[Aric Dunn]

Looks like gfs has it hanging around a long time near florida. Then finally off to the NE. Always worth watching. Given its location it will take some time though being in the trough axis.

[northjaxpro]

This disturbed area is in a pretty decent low shear environment for the time being. 10-15 kt shown around the Central Bahamas. This has an opportunity to try to develop.

[DioBrando]

This disturbed area is in a pretty decent low shear environment for the time being. 10-15 kt shown around the Central Bahamas. This has an opportunity to try to develop.

You reckon this might become Chantal quickly?

[wxman57]

Surface obs indicate relatively high pressure across the Bahamas (1017-1018mb). Nothing at the surface.

[toad strangler]

Surface obs indicate relatively high pressure across the Bahamas (1017-1018mb). Nothing at the surface.

Yeah that's shorts and flip flops pressures

[northjaxpro]

Surface obs indicate relatively high pressure across the Bahamas (1017-1018mb). Nothing at the surface.

Yeah for now 57. I checked them earlier in the region. We will see how this will fare as time progresses.

[DioBrando]

Whatever, not gonna bother with this. Next.

[northjaxpro]

Surface trough axis continues from the NW Bahamas southward to the Florida Straits, per 21Z surface analysis of NHC/WPC.

This area still warrants monitoring the next few days.

[northjaxpro]

This disturbed area is in a pretty decent low shear environment for the time being. 10-15 kt shown around the Central Bahamas. This has an opportunity to try to develop.

You reckon this might become Chantal quickly?

Pressures are still high in the region , and models have yet to jump full fledge on development yet. However, this still needs to be watched as any energy(vorticity) hanging around plenty warm ssts needs to always be monitored, especially in this area of the basin. It is in a pocket of rather light wind shear down there too as I mentioned earlier today (10-15 kts) currently.

Just an area of interest to watch for now.

[northjaxpro]

DMAX at its best overnight.

A very strong and impressive MCS developed after midnight and currently is situated on the tail end of the trough axis over the Florida Straits, midway between the North coast of Cuba and Andros Island.

Very cold cloud tops with the feature earlier. Low wind shear currently and very warm ssts in that region.

If given a sweet spot, this system could thrive, and I think it just may have started doing so. This could spin down a surface reflection quickly. Closely watch throughout the short term ...

[GCANE]

I saw this morning's GFS Legacy showing a 850mb vort development north of Cuba in the next couple days.
It has it moving thru the Straits of FL Friday and into the GOM over the weekend.

[northjaxpro]

I saw this morning's GFS Legacy showing a 850mb vort development north of Cuba in the next couple days.
It has it moving thru the Straits of FL Friday and into the GOM over the weekend.

Looking at the cold convective cloud tops on satellite imagery re- firing just off the North Coast of Cuba this morning currently, I think we could be seeing the makings of this GCANE a bit sooner. Also, strong convective cells re-firing just to the south/southeast of Andris Island at this hour.

This feature definitely could emerge into the Southeast Gulf of Mexico by Friday.

[NDG]

At least for the next few days I only see a disturbance interacting with a trough weak ULL as an UL ridge builds over the central GOM. It will be very slow to develop into anything. IMO.

[northjaxpro]

At least for the next few days I only see a disturbance interacting with a trough weak ULL as an UL ridge builds over the central GOM. It will be very slow to develop into anything. IMO.

Development, would be slow, but if 850 mb vorticity increases or maintains as this feature moves through the Florida Straits the next couple of days, then I give it decent chances to potentially develop, once it emerges into the SE GOM.