ATL: INVEST 91L - Discussion

[tropicwatch]

Now some of the models are initiating on the wave with a 40% chance of development and some of them are on the wave with a 70% chance of development. Don't think I have ever seen this before. 2020 at its best.

https://my.sfwmd.gov/sfwmd/common/images/weather/plots/storm_91.gif

[cycloneye]

A broad area of low pressure located over the eastern tropical
Atlantic several hundred miles west-southwest of the Cabo Verde
Islands is producing a small area of disorganized showers and
thunderstorms. Gradual development is possible early next week once
the larger tropical wave located off of the coast of Africa passes
to the north of the system on Sunday.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...medium...40 percent.

[Aric Dunn]

91L is nearly completely strung out.. waves near Africa have pretty much merged and central convection taking over..

hopefully they tag the other area as an invest in the morning so we can kill this thread.

[ClarCari]

91L is nearly completely strung out.. waves near Africa have pretty much merged and central convection taking over..

hopefully they tag the other area as an invest in the morning so we can kill this thread.


https://i.ibb.co/nwpCKpQ/Capture.png

Well since it seems like they were planning for these to merge would they still wait for it and keep the whole thing as 91L or would they really re-tag it?

[Aric Dunn]

91L is nearly completely strung out.. waves near Africa have pretty much merged and central convection taking over..

hopefully they tag the other area as an invest in the morning so we can kill this thread.


https://i.ibb.co/nwpCKpQ/Capture.png

Well since it seems like they were planning for these to merge would they still wait for it and keep the whole thing as 91L or would they really re-tag it?

models were taking much much longer to merge these two. its already done..

[GCANE]

Following ICON and GFS, there actually maybe something to this.
IR Satellite Analysis currently puts the LL CoC at 12N 36.5W
That is where ICON has it.
ICON keeps it rolling for 102 hrs to about 15N 50W.
That is where GFS picks it up as a strong warm core and moves it toward the Bahamas.
Definitely watching this one.

[GCANE]

GFS retrogrades 91L's LL Vort to the NE and merges with the huge TPW roll.

[GCANE]

102 hrs out, on the SW side of a TUTT.
Good setup for development.

[GCANE]

Need to watch that big-ass polar-vortex driven Rossby Wave / negative-tilt trof sweeping across CONUS once the LLC gets in the Bahamas.
Could run into an ULL ahead of it where it could get sheared apart or it could be running into a Anticyclone Rossby Wave Break where it could ramp up.
How that Rossby Wave evolves is going to be key.

[Aric Dunn]

Say bye bye to 91l.

It is but a stretched out ITCZ vorticity. and should be all but gone soon.

time for the powers at be to invest the large wave to the east now..

[Blinhart]

I'm guessing the reason that no models or anything is making sense with this is because there are 4 separate waves that have a potential to form, and we won't know until we have a confirmed CoC or two or three or four.

[BensonTCwatcher]

Yeah hard to model this setup, but looking more and more like a New Invest coming

[sma10]

I'm guessing the reason that no models or anything is making sense with this is because there are 4 separate waves that have a potential to form, and we won't know until we have a confirmed CoC or two or three or four.

Borrowing a phrase from many NHC discussions .... "confidence level currently low on future tracks"

[us89]

NHC keeping this at 20/30 for now:

2. A nearly stationary broad area of low pressure is located over the
east-central tropical Atlantic about midway between the west coast
of Africa and the Windward Islands. This system continues to
produce disorganized showers and thunderstorms, and some
development is possible during the next couple of days before it
merges or interacts with a large tropical wave located to its east.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...low...30 percent.

[abajan]

Down to 20/20 in the 2 AM TWO:

A nearly stationary and poorly-defined area of low pressure is
located over the east-central tropical Atlantic about midway
between the west coast of Africa and the Windward Islands. This
system continues to produce disorganized showers and thunderstorms,
and development will likely be hindered by the interaction
with a large tropical wave located just west of the Cabo
Verde Islands.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...low...20 percent.

[us89]

And down even further to 10/10 in the 8 AM:

1. Shower activity has become less organized in association with a
trough of low pressure located about midway between the west coast
of Africa and the Windward Islands. Significant development
of this system is not expected, as it will likely be hindered by
the interaction with a large tropical wave located a few hundred
miles to its east.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...10 percent.

[cycloneye]

Is no longer being updated on the ATCF files so bye.