ATL: Ex INVEST 99L - Discussion

[ScottNAtlanta]

That area over the Yucatan is also interesting

[Teban54]

Convection is kicking up again but vorticity not so much.

Not so much, but it is still there, and convection is firing. If it can keep this up until the West Caribbean there could be something happening

Even in the model runs from days earlier when some ensemble members were developing it, typically only the stronger members in the near term end up moving north into the Gulf. My guess is that even if the low levels improve in Western Caribbean, it's more likely to crash into Central America and/or develop in EPac. The best-case scenarios would then be something like Bonnie 2022 or Nadine & Kristy 2024.

[Weathertracker96]

https://i.imgur.com/07z4GBb.gif

That area over the Yucatan is also interesting

Could be interesting if that & 99L tries to merge.

[Ptarmigan]

I am not going to write off Invest 99L yet.

[Stratton23]

is it possible for the stalled front in the gulf , that it could help to drag up 99L’s moisture pool into the gulf? Also see that interesting area of convection about to enter the BOC

[BobHarlem]

Remnants of this are heavily sheared, very elongated west to east, and the mid level is stretched out down to south America. I don't see a way for this to come back, the NHC made the right call. Land interaction may restart the spin for the east Pacific, however.

[Weathertracker96]

is it possible for the stalled front in the gulf , that it could help to drag up 99L’s moisture pool into the gulf? Also see that interesting area of convection about to enter the BOC

I agree. Something to keep watch especially if conditions are good around then.

[cycloneye]

NHC added area of interest just off CentralAmerica and Mexican coasts and this has to be somewhat related to some energy from ex99L.

[zhukm29]

Found this interesting post that was made a few days ago that might lead to some more credence that 99L was a TC at some point during its lifetime for post season analysis.

TL;DR - the user hypothesizes that 99L had a small vortex that was not detected by ASCAT when it was moving through the MDR, given how long it lasted beyond what the models initially predicted. Usually if the models keep on insisting that a system will die immediately and the system doesn’t die for days on end, something could be happening that the models may not be picking up on. We’ve had this before with systems like Oscar ‘24 and Nana ‘20 where ASCAT showed nothing but a subsequent recon plane found a small but well defined LLC. Obviously this is just a hypothesis, but it does go back to the idea of “if it looks like a TC and behaves like a TC, then it might actually be a TC” - and the models trying to kill off the system prematurely might not have had enough resolution to detect a potential vortex that could be keeping the system alive longer than expected.

 https://x.com/bryan_maxw46284/status/1959354871540322498