Tropical Wave in Bay of Campeche (Is Invest 91L)

[Teban54]

(Edit: Added 6z EPS.)

GEFS member low pressure counts (±2, out of 31):

• 6z 8/27: 14 (45%)
• 0z 8/27: 9 (29%)
• 18z 8/26: 19 (61%)
• 12z 8/26: 17 (55%)
• 6z 8/26: 19 (61%)
• 0z 8/26: 16 (52%)
• 18z 8/25: 10 (32%)
• 12z 8/25: 14 (45%)

EPS member low pressure counts (±3, out of 51):

• 6z 8/27 (out to 144 hrs only): 20 (39%)
• 0z 8/27: 25 (49%)
• 18z 8/26 (out to 144 hrs only): 27 (53%)
• 12z 8/26: 34 (67%)
• 0z 8/26: 22 (43%)
• 12z 8/25: 11 (22%)

Other than the brief dip that was 0z 8/27 GEFS, I'd say the ensemble support remains pretty good, even if not as high as 12z/18z yesterday. The differences are within the range of rounding errors and/or a few lows without actual TC development.

What's also interesting is that 0z EPS has a few members showing a Laura-like or Grace-like track, where the wave develops in the MDR but treks through the Greater Antilles before bombing out in the BoC.

Edit: Also, 6z GEFS is much further SW in track than 18z and 12z. Whether that's because of delayed development or correction in ridge strength, I don't know.

[IsabelaWeather]

NHC pulled the trigger too soon for this lemon?

What do you mean, its an AOI, not a PTC or something. It currently has better odds not to develop than develop.

[skyline385]

it is very surprising that people still seem to misinterpret what the NHC AOI means, seeing a lot of posts everywhere (not just on S2K) that NHC pulled the trigger early even though there are currently more than 20% members on both GEFS and EPS showing a TC formation within 7 days. The lemon is perfectly fine.

[DorkyMcDorkface]

And 06z GFS still has no development and ensembles also trended much weaker as well. Wtaf is going on.

Based on 0z and 6z runs along with satellite, would not be surprised to see this lemon go to 0/10 and then if 12z still shows nothing, then removed all together. As far a model performances this summer. To this point models have been fairly accurate. When no modeling and no storms. Now if there was no modeling and storms blew up, then we might have something to discuss.

The pathway to TCG is more complex than usual with the monsoon trough breakdown rather than a straightforward TW. Models almost always have difficulty resolving these setups, which is why I wouldn't put too much stock into any radical fluctuations in intensity, track, etc. at this juncture.

[CronkPSU]

NHC pulled the trigger too soon for this lemon?

they give it a 0-20% chance of forming....sounds right to me

[toad strangler]

NHC pulled the trigger too soon for this lemon?

they give it a 0-20% chance of forming....sounds right to me

Is that a 0-20% chance there will be wxman57 Labor Day vaca cancel?

[TomballEd]

While EPS had a false alarm a couple of weeks ago, the Euro ensembles have been seeing the real future TCs earlier than the GFS and ensembles. I have a theory, ECENS run same resolution as the op, GEFS run half the resolution of the GFS, or GEFS may have more trouble resolving more nuanced development. Not like the GEFS have abandoned it.

Strong EPS signature for TCG by day 7 in MDR, or NHC didn't pull the trigger too soon on a 7 day lemon.

[ChrisH-UK]

Woops wrong place

[Teban54]

Looked real nice at dawn with a lot of convection then it got blown off.

Source - https://col.st/LtPUz

[url]https://imagizer.imageshack.com/img922/1603/JP3c09.gif [/url]

I believe you posted in the wrong thread? There's another thread for it.

[ChrisH-UK]

Looked real nice at dawn with a lot of convection then it got blown off.

Source - https://col.st/LtPUz

[url]https://imagizer.imageshack.com/img922/1603/JP3c09.gif [/url]

I believe you posted in the wrong thread? There's another thread for it.

Just realised and fixed

[cycloneye]

 https://x.com/AndyHazelton/status/1828425358502223994

[wxman57]

NHC pulled the trigger too soon for this lemon?

they give it a 0-20% chance of forming....sounds right to me

Is that a 0-20% chance there will be wxman57 Labor Day vaca cancel?

Nah, no issue for my days off. Models are backing off on any development overnight. Best chance of development may be off the East U.S. Coast in a week or so along a front.

[Stratton23]

Its way to soon to be writing off this wave

[cycloneye]

Once again ICON develops in NE Caribbean islands.

[Category5Kaiju]

In terms of major recent examples, I wonder if model-wise, this could play out like Dorian or Fiona, where ensembles were really the first to detect it but didn’t give off a major signal at first, only for such to dramatically increase closer to the time of development.

[cheezyWXguy]

Once again ICON develops in NE Caribbean islands.

https://i.imgur.com/iq5VZAL.png

This run’s feedback loops over Africa are…interesting. It has an inland ts at 991mb over Western Africa

[Hurricane2022]

As noted here and elsewhere, it is possible that these model-generated African ghost storms may be absorbing the tropical waves that would evolve into a mature cyclone later in these runs.. This is quite interesting.

I still think that this system will likely be Francine in the Future.

[LarryWx]

 https://x.com/AndyHazelton/status/1828425358502223994

Ernesto’s AEW also had very little convection until it started approaching the NE Caribbean, which is what the models were showing.

[WaveBreaking]

What really determines how well this AOI does is if it doesn’t get overtaken by a vigorous wave right behind it. Only the gfs shows this rn, and it has a history of prematurely stringing waves out, so I think the disturbance can get itself together and not be affected by the approaching wave.

[Teban54]

A bit more convection firing during the last few hours: