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

[SFLcane]

The EPS suggests to me fwiw an increased threat to the U.S. Gulf coast from the lemon vs earlier runs.

Can you post the mslp maps not home lol.

I can’t as it is from a paid site. I thought you were looking at them, yourself, per your post.

I am lol.. seems like we are playing this up and down game with both the ops and ensembles models seems like for a few weeks now maybe there is nothing overnight again.

[SFLcane]

[Ivanhater]

This is what I mentioned yesterday. If this struggles to develop until Western Caribbean/Bahamas, then it is game on for US and Gulf

[aspen]

Operational Euro has the wave slide basically due west into the WCar. Perhaps it may have a chance past 60-70W?

[Weathertracker96]

This is what I mentioned yesterday. If this struggles to develop until Western Caribbean/Bahamas, then it is game on for US and Gulf

I agree with you. With this system possibly waiting to develop and getting in the Caribbean would be trouble. The same steering that could bring it OTS would curve this one up into the Gulf or FL.

I know it’s early but has the Caribbean been more favorable than the MDR lately?

[SFLcane]

[MEANINGLESS_NUMBERS]

Well this is great news for Bermuda.

[Stratton23]

Of course when the 18z OP GFS goes back to dropping it, now the 18z GEFS has a noticeable uptick in support lol

[cheezyWXguy]

Woah, 18z gefs bringing the fire back

[Teban54]

This loop says it all:



Edit: However, the caveat is that the disturbance was more convectively active when the 18z run was initialized than it is now. It looks like vorticity at all levels have also become a little bit more disorganized. There's a chance that 18z initializations were picking up on the increase in organization and extrapolating it to later hours, and that 0z may similarly become less active. Of course, this can also be just the windshield wiper effect.

[SFLcane]

Woah, 18z gefs bringing the fire back

!!

[MarioProtVI]

This loop says it all:

https://i.postimg.cc/Px9wvvJ5/gfs-ememb-lowlocs-atl-fh180-trend.gif

Starting to think this windshield wiper effect will continue until the models can latch onto an actual coherent entity because it seems right now the up and down in support seems to be highly dependent on it separating enough from the monsoon trough to not be swept into the vorticity of the eastern AEW on models.

[Teban54]

This loop says it all:

https://i.postimg.cc/Px9wvvJ5/gfs-ememb-lowlocs-atl-fh180-trend.gif

Starting to think this windshield wiper effect will continue until the models can latch onto an actual coherent entity because it seems right now the up and down in support seems to be highly dependent on it separating enough from the monsoon trough to not be swept into the vorticity of the eastern AEW on models.

Lol, that's almost what I said in the edit

[cycloneye]

Edited the title to add "Tropical Wave".

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Wed Aug 28 2024

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

1. Central Tropical Atlantic:
A broad area of disorganized showers over the central Tropical
Atlantic are associated with a tropical wave. Some slow development
of this system is possible this weekend into the middle of next week
while it moves westward to west-northwestward at 10 to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.


Forecaster Papin

[LarryWx]

Edited the title to add "Tropical Wave".

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Wed Aug 28 2024

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

1. Central Tropical Atlantic:
A broad area of disorganized showers over the central Tropical
Atlantic are associated with a tropical wave. Some slow development
of this system is possible this weekend into the middle of next week
while it moves westward to west-northwestward at 10 to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.


Forecaster Papin

It’s moving a little slower than the avg wave, which is closer to 15. This one is only 10-15.

[Ubuntwo]

18z EPS looks like an uptick with ~40% of members with a TS by day 7. The GEFS similarly ticked up to ~35% at 18z, climbing later in the run. Windshield wipering or the start of a trend?

[LarryWx]

18z EPS looks like an uptick with ~40% of members with a TS by day 7. The GEFS similarly ticked up to ~35% at 18z, climbing later in the run. Windshield wipering or the start of a trend?

Per my eyeballs, I count at least 13 of the 31 GEFS members on TT with a TC. And based on more eyeballing, this looks like the most active from the current lemon since the 18Z two days ago. I wouldn’t read too much into this though as it could just be a one off run. Let’s see what 0Z shows.

I know Teban has been counting more closely the members. Is this the most active for just the lemon since the 6Z of 8/26?

[Spacecoast]

From the 12z EPS @336Hour....


Is that 918 mb??
Very strong.

[Teban54]

18z EPS looks like an uptick with ~40% of members with a TS by day 7. The GEFS similarly ticked up to ~35% at 18z, climbing later in the run. Windshield wipering or the start of a trend?

Per my eyeballs, I count at least 13 of the 31 GEFS members on TT with a TC. And based on more eyeballing, this looks like the most active from the current lemon since the 18Z two days ago. I wouldn’t read too much into this though as it could just be a one off run. Let’s see what 0Z shows.

I know Teban has been counting more closely the members. Is this the most active for just the lemon since the 6Z of 8/26?

Glad there's still interest! To be honest, I kind of skipped 12z because it was hard to tell the members that developed this wave past Lesser Antilles, but let me try again.

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

• 18z 8/28: 13 (42%) as of Eastern Caribbean
• 12z 8/28: 7 (23%) as of Eastern Caribbean (a few members start in WCar, but unsure if they're from this wave or a CAG)
• 6z 8/28: 9 (29%)
• 0z 8/28: 9 (29%)
• 18z 8/27: 4 (13%)
• 12z 8/27: 9 (29%)
• 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):

• 18z 8/28 (out to 144 hrs only): 33 (65%, some may not be TCs)
• 12z 8/28: 18 (35%) as of Eastern Caribbean (a few members dissipate there, a few develop in WCar)
• 6z 8/28 (out to 144 hrs only): 21 (41%, some may not be TCs)
• 0z 8/28: 11 (22%)
• 18z 8/27 (out to 144 hrs only): 15 (29%)
• 12z 8/27: 14 (27%)
• 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%)

Today's 18z EPS is close to the most active run ever (that's 12z 8/26), though that's helped by a few members that seem to only have the low form in Eastern Caribbean. Note that not all of these systems are TCs, never mind TSes. On the other hand, some members may also only develop the wave once it gets to Western Caribbean or the Gulf.

18z GEFS is the most active over the past 6 runs, but still less so than the most active day ever (8/26). However, it's a quality-over-quantity situation, as the members that do form are pretty strong as they hit or brush the Caribbean islands.

[TomballEd]

18z EPS looks like an uptick with ~40% of members with a TS by day 7. The GEFS similarly ticked up to ~35% at 18z, climbing later in the run. Windshield wipering or the start of a trend?