Low Pressure Trough Over the Central Atlantic (Is Invest 99L)

[cycloneye]

There is some turning in the clouds.

[ChrisH-UK]

The view from Meteosat-10, looks to be curling up.

Source - https://col.st/lV3kE

[zzzh]

Edge pass, take it with a grain of salt.

[cycloneye]

NHC adds low pressure at 12z surface analysis.

[Nimbus]

12Z GFS initialized this about a half degree too far north but keeps it tracking west where it crosses the 18N near -50W
There is a ridge to the north so we can wait and see if it passes inside of Bermuda this run or not.

[gatorcane]

1/2 a degree too far north or not, the GFS has a significant trough over the Western Atlantic. It has to recurve with that kind of setup. We should not be surprised as the Bermuda High has been weak most of the summer.

[LarryWx]

12Z UKMET again develops this into a TS. It hits the Leewards to PR followed by a recurve E of the Bahamas to a position that could later threaten Bermuda:

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 90 HOURS
FORECAST POSITION AT T+ 90 : 16.2N 59.1W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
1200UTC 20.08.2023 96 16.7N 60.2W 1005 34
0000UTC 21.08.2023 108 17.3N 62.1W 1005 35
1200UTC 21.08.2023 120 18.4N 64.4W 1004 36
0000UTC 22.08.2023 132 19.8N 65.4W 1004 40
1200UTC 22.08.2023 144 21.2N 67.5W 1004 45
0000UTC 23.08.2023 156 22.2N 67.5W 1003 41
1200UTC 23.08.2023 168 24.5N 68.2W 1004 40

[Spacecoast]

12z GEFS Trough prob: double edge sword, attracting both Cent ATL Low, (and members (about 40%) from the 'CAG' group).

[Blown Away]

12z Euro trend... No way anyone can have confidence in these models when they can't resolve these lows gyre... JMHO

[SFLcane]

[url]https://i.postimg.cc/c1BgrJ1x/ed29d882-5921-46d4-9574-7546a68c6caf.gif [/url]
12z Euro trend... No way anyone can have confidence in these models when they can't resolve these lows gyre... JMHO

[Ianswfl]

[url]https://i.postimg.cc/c1BgrJ1x/ed29d882-5921-46d4-9574-7546a68c6caf.gif [/url]
12z Euro trend... No way anyone can have confidence in these models when they can't resolve these lows gyre... JMHO

https://i.postimg.cc/6QG3fWdm/gggg.png

The cat4 member over Miami is that from the possible carribean system or the mid atl one?

[jlauderdal]

[url]https://i.postimg.cc/c1BgrJ1x/ed29d882-5921-46d4-9574-7546a68c6caf.gif [/url]
12z Euro trend... No way anyone can have confidence in these models when they can't resolve these lows gyre... JMHO

https://i.postimg.cc/6QG3fWdm/gggg.png

Activity over sofla at long range isn't unusual, been there many many times. No doubt the models have down an about-face the last few days with activity but certainly far from laser-focused on solutions.

[Woofde]

1/2 a degree too far north or not, the GFS has a significant trough over the Western Atlantic. It has to recurve with that kind of setup. We should not be surprised as the Bermuda High has been weak most of the summer.

That definitely screams recurve, but it is also 7 days in the future. I have 0 confidence in any modeling that far out. The average error that many days out is hundreds of miles.

[Teban54]

1. Central Tropical Atlantic:
Disorganized showers and thunderstorms continue in association with
an elongated trough of low pressure centered about 750 miles
west-southwest of the Cabo Verde Islands. Environmental conditions
appear conducive for gradual development of this system, and a
tropical depression could form during the next several days while it
moves westward or west-northwestward at about 10 mph across the
central tropical Atlantic.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...medium...50 percent.

[ElectricStorm]

Last two GFS runs have really backed off and don't show much development, after multiple runs showing a hurricane.

[LarryWx]

TWO: now up to 40%/60%

0Z UKMET: yet again a TS in the Leewards, but this run then has it go NNW and later NNE track that aims well to the E of Bermuda:

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 84 HOURS
FORECAST POSITION AT T+ 84 : 16.9N 58.9W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
1200UTC 20.08.2023 84 16.9N 58.9W 1006 28
0000UTC 21.08.2023 96 17.6N 60.3W 1005 34
1200UTC 21.08.2023 108 19.2N 60.9W 1005 42
0000UTC 22.08.2023 120 20.2N 61.4W 1003 39
1200UTC 22.08.2023 132 22.0N 61.8W 1003 44
0000UTC 23.08.2023 144 23.8N 62.3W 1004 35
1200UTC 23.08.2023 156 25.6N 61.8W 1005 31
0000UTC 24.08.2023 168 26.9N 60.9W 1004 27

[ouragans]

Invest 99L is up