ATL: NANA - Remnants - Discussion

[Hammy]

~12 hours apart. Should close off by tomorrow evening if not sooner at this rate.

[CourierPR]

Local Miami Met., Craig Setzer, on WFOR showed models that have 99L taking a southwest track. I was very surprised.

[cfisher]

https://i.imgur.com/EqTxmUd.png

~12 hours apart. Should close off by tomorrow evening if not sooner at this rate.

What latitude would it close up at?

[tailgater]

1. A seemingly well-organized cluster of showers and thunderstorms
associated with a tropical wave is moving quickly westward across
the central Caribbean Sea, but satellite-derived wind data from a
few hours ago again showed that the system has not developed a
closed surface wind circulation. The wave is, however, producing
an area of winds near tropical storm force south of the coast of
Haiti, which will move near or south of Jamaica later this morning.
Environmental conditions are expected to become a little more
conducive for development, and a tropical depression is likely to
form during the next couple of days before the system reaches
Central America Wednesday night. Locally heavy rains and gusty
winds are possible on Jamaica today, and interests there, as well as
in northern Nicaragua, Honduras, Belize, Guatemala, and the Yucatan
Peninsula, should monitor the progress of this disturbance.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...70 percent.

[Visioen]

This system has been teasing us with its looks. Contrary to the circulation, I'm down to earth again.

[Hammy]

https://i.imgur.com/EqTxmUd.png

~12 hours apart. Should close off by tomorrow evening if not sooner at this rate.

What latitude would it close up at?

Given the motion and where the easterly winds have decreased from earlier, I'd personally estimate somewhere between 13 and 14.5 N

[EquusStorm]

Without scatterometer data you'd think this was a strong tropical storm. Definitely by far the best looking wave/invest of the year beating out Zombie 94L. Could still work its way down, who knows.

[cfisher]

Without scatterometer data you'd think this was a strong tropical storm. Definitely by far the best looking wave/invest of the year beating out Zombie 94L. Could still work its way down, who knows.

What's stopping the MLC from working it's way down? There was some dry air but it seems to be working it out

[Hammy]

Without scatterometer data you'd think this was a strong tropical storm. Definitely by far the best looking wave/invest of the year beating out Zombie 94L. Could still work its way down, who knows.

What's stopping the MLC from working it's way down? There was some dry air but it seems to be working it out

Forward speed more than likely

[Hammy]

Analyzed low cloud motion, this is more disorganized than I realized and seems like it's getting hammered with easterly shear. Wave axis and where the storm-relative center is.

[GCANE]

IR Satellite analysis puts the boundary-layer vort CoC on the I in the 2nd graphic below.
From WV-satellite, I estimate the ML CoC to be NNW of that.
CIMSS shows the Anticyclone CoC to be NW of the ML CoC.
Obviously vort column is tilted to the NW.
Surface obs seems to indicate a wave axis tilted nearly north to south.

[cfisher]

IR Satellite analysis puts the boundary-layer vort CoC on the I in the 2nd graphic below.
From WV-satellite, I estimate the ML CoC to be NNW of that.
CIMSS shows the Anticyclone CoC to be NW of the ML CoC.
Obviously vort column is tilted to the NW.
Surface obs seems to indicate a wave axis tilted nearly north to south.

https://i.imgur.com/s1VQzc2.gif

https://i.imgur.com/gMqXThw.png

We're probably just waiting on ASCAT to confirm a surface low has formed near the MLC.

[cfisher]

Pretty impressive structure considering N inflow is being blocked by Jamaica.

[GCANE]

IR Satellite analysis puts the boundary-layer vort CoC on the I in the 2nd graphic below.
From WV-satellite, I estimate the ML CoC to be NNW of that.
CIMSS shows the Anticyclone CoC to be NW of the ML CoC.
Obviously vort column is tilted to the NW.
Surface obs seems to indicate a wave axis tilted nearly north to south.

https://i.imgur.com/s1VQzc2.gif

https://i.imgur.com/gMqXThw.png

We're probably just waiting on ASCAT to confirm a surface low has formed near the MLC.

Recon on the way

[Aric Dunn]

We just went through this with Marco and Laura... ASCAT not being able to close of a LLC but recon does..

I would bet money this has been a TD/TS since yesterday.

[cfisher]

[crownweather]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Tue Sep 1 2020

A well-organized cluster of showers and thunderstorms associated
with a tropical wave continues to move quickly westward across the
central Caribbean Sea. Although the disturbance does not yet have a
well-defined circulation center, ship observations indicate that
tropical-storm-force winds are occurring in the northern portion of
wave to the southeast of Jamaica, which will spread near or just
south of Jamaica later this morning and into this afternoon.
Environmental conditions are expected to become a little more
conducive for development, and a tropical depression or a tropical
storm is likely to form during the next day or so before the
system reaches Central America Wednesday night. Locally heavy rains
and gusty winds are possible on Jamaica today, and interests there,
as well as in northern Nicaragua, Honduras, Belize, Guatemala, and
the Yucatan Peninsula, should monitor the progress of this system.
An Air Force Reserve reconnaissance aircraft is currently en route
to investigate the disturbance.

Potential tropical cyclone or tropical cyclone advisories will
likely be issued later today, along with watches and warnings.
Additional information on this system can be found in High Seas
Forecasts issued by the National Weather Service.

* Formation chance through 48 hours...high...80 percent.
* Formation chance through 5 days...high...80 percent.

[Sciencerocks]

[Aric Dunn]

meso floater is up
https://www.tropicaltidbits.com/sat/sat ... roduct=vis
you can see easterly moving clouds well away from the where the center is. under that deep convection SE side of Jamainca.

going to be a small Tight LLC which is why ASCAT cant pick up on it again.

[NDG]

It may not be until it gets to the Gulf of Honduras tomorrow before a surface circulation really gets going, the central Caribbean is usually a hard place for a TW to develop because of the usual fast diverging winds at the surface when the fast easterlies are still present this time of the year..
So the usual saying is true that if a TW does not develop near the Windward Islands then it will not develop until it gets to at least the western Caribbean.