Tropical Wave over the Central Atlantic (Is Invest 96L)

[cycloneye]

Up to 40%.

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Wed Jul 26 2023

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

Eastern Atlantic:
A tropical wave is located a couple of hundred miles to the
southwest of the Cabo Verde Islands. Conditions are expected to be
favorable for gradual development of this system later this
week, and a tropical depression could form over the weekend or
early next week while it moves westward to west-northwestward over
the tropical Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...40 percent.

$$
Forecaster Beven

[Iceresistance]

Up to 40%.

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Wed Jul 26 2023

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

Eastern Atlantic:
A tropical wave is located a couple of hundred miles to the
southwest of the Cabo Verde Islands. Conditions are expected to be
favorable for gradual development of this system later this
week, and a tropical depression could form over the weekend or
early next week while it moves westward to west-northwestward over
the tropical Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...40 percent.

$$
Forecaster Beven

https://i.imgur.com/wsuZv8r.png

Code Orange!

[Category5Kaiju]

It's honestly wild that literally two days ago, there were talks of this wave busting and this season being in jeopardy of producing the above average, non-Nino-like activity that experts have been forecasting. I even saw people on social media saying that this season was done and that Don was the strongest hurricane of the season.

Now not only are many models expecting this new wave to form into a TC, but it also looks to be potentially a strong, Cat 2 or 3 recurving system that produces considerable ACE.

It's almost as if the Atlantic Ocean "heard" the bust-casters and got irritated

[wxman57]

I would say development chances are above 50%.

I agree, good model support now - not just the GFS. I do think the GFS is way overdoing the intensity, though. Could possibly threaten Bermuda, but not likely a Caribbean or U.S. threat. I think this type of track will be common this year with a weaker Bermuda high. Unfortunately, not all systems will have a trof to steer them away from the Bahamas and SE U.S.

[SFLcane]

I would say development chances are above 50%.

I agree, good model support now - not just the GFS. I do think the GFS is way overdoing the intensity, though. Could possibly threaten Bermuda, but not likely a Caribbean or U.S. threat. I think this type of track will be common this year with a weaker Bermuda high. Unfortunately, not all systems will have a trof to steer them away from the Bahamas and SE U.S.

I was gonna say that’s not quite what your outlook was a few months ago. You were concerned about the ne Caribbean, Bahamas and Florida. I do agree it’s only July and we are yet to enter the “ REAL “ capeverde season. Quite interesting we could be looking at 2 hurricanes for July not to shabby for a strengthening El Niño lol.

[gatorcane]

Quite a trough that the models think will turn this system north and northeast, 40s across the northeast which is quite a bit below normal. Good timing on the trough if this verifies (assuming Bermuda is spared):

[Hybridstorm_November2001]

In my area of SE Maine/SW New Brunswick, we've had dew points averaging in the low 70s most days since June 20th. The dew points of around 50 behind those two troughs (one coming this weekend and the other next week) are looking mighty fine.

[ElectricStorm]

Definitely better overall model support now, which means development of this wave is much more believable than it was a couple days ago. I think NHC will continue to raise the chances in upcoming TWO's and this probably has a good chance to become Emily.

Not sure about hurricane chances though, would like to see better model support for that. Although I didn't expect Don to become one so we'll see.

[Teban54]

Current ensemble support for the wave:

• 12z GEFS: At least 16 members (52%) show some development, with 8 members showing a hurricane. All recurves before the islands.
• 6z GEFS: 11 members (35%) show some development, with 6 members showing a hurricane. Most are recurves, with 3 members heading into the Caribbean and dissipating there.
• 0z GEFS: At leats 18 members (58%) show some development, with 11 members showing a hurricane. Most are recurves, but 2 members take the Mona Passage (both Hs) and hit SE Bahamas; no CONUS threats.
• 6z EPS: At the end of the run (144 hr), at least 28 members (55%) show some development or at least a low.
• 0z EPS: At least 29 members (57%) show some development, with 6 members showing a hurricane. Almost all are recurves, but one member heads WNW east of the Bahamas.

There may be some undercounting for Euro ensembles, as they're hard to see on the map.

• 18z GEFS: 13 members (62%) show some development, but with only 1 hurricane (though there are 3 Hs from a trailing wave). A lot further west than 12z, with many TS landfalls in LA and even a TS landfall in SE FL.
• 12z EPS: At least 27 members (53%) show some development, with 5-7 hurricanes (some are in the high latitudes so doubtful). Tracks are a lot further E than 0z.
• 18z EPS: At least 26 members (51%) show some development at 144 hr.

0z GEFS was by far the most active, with at least 28 members (90%) show some development, and 17 hurricanes. Almost all are recurves, with one member clipping LA and going through the Bahamas.

6z GEFS is only a tiny bit less active, with at least 25 members (81%) show some development, and 17 hurricanes. One H clips the NC Outer Banks, but otherwise all recuves.

0z EPS was a lot less active than earlier runs, with at least 19 members (37%) show some development, and only 3-4 hurricanes.

However, 6z EPS went back to the earlier levels, with at least 29 members (57%) show some development through 144 hrs.

18z EPS has at least 41 members (80%). 18z GEFS has at least 24 members (77%). 12z GEFS has at least 26 members (84%).

So ensembles seem to be all on board now. I'll probably stop counting ensemble members given how tedious it is, unless things change significantly.

[Teban54]

Looks like GFS is correcting its overly aggressive solutions, as shown below. I think that's still better than not developing at all until 2-3 days out.

[abajan]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 AM EDT Thu Jul 27 2023

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

1. Eastern Atlantic:
A tropical wave is located a few hundred miles to the southwest of
the Cabo Verde Islands. Conditions are expected to be favorable
for gradual development of this system later this week, and a
tropical depression could form over the weekend or early next week
while it moves westward to west-northwestward over the tropical
Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...40 percent.

Forecaster Beven

[abajan]

The 6z GFS is much weaker than previous runs, and is in fairly good agreement with the 0z Euro:

[abajan]

As expected, there's been no change in formation chances:

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Thu Jul 27 2023

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

1. Eastern Atlantic:
A tropical wave is located several hundred miles to the southwest of
the Cabo Verde Islands. Conditions are expected to be favorable for
gradual development of this system later this week, and a tropical
depression could form over the weekend or early next week while it
moves westward to west-northwestward over the tropical Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...40 percent.

Forecaster Pasch

[jlauderdal]

As expected, there's been no change in formation chances:

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Thu Jul 27 2023

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

1. Eastern Atlantic:
A tropical wave is located several hundred miles to the southwest of
the Cabo Verde Islands. Conditions are expected to be favorable for
gradual development of this system later this week, and a tropical
depression could form over the weekend or early next week while it
moves westward to west-northwestward over the tropical Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...40 percent.

Forecaster Pasch

https://images2.imgbox.com/d6/9d/aOjdBW09_o.png

A Mandarin Fish-trough saved us this time

I had a rain rate of 5.29 this morning, 3.13 so far from the Bahamas wave. Fun times in sofla this summer, lots of heat, humidity and precip.

[cycloneye]

 https://twitter.com/AndyHazelton/status/1684557893251796995

[Category5Kaiju]

https://twitter.com/AndyHazelton/status/1684557893251796995

One thing I have noticed is that that weak 6z GFS run also features a parade of EPAC storms; the earlier models that had this system grow stronger did not feature such an active EPAC. Not 100% what caused the GFS to all of a sudden think the EPAC would light up this time, however.

[wxman57]

https://twitter.com/AndyHazelton/status/1684557893251796995

One thing I have noticed is that that weak 6z GFS run also features a parade of EPAC storms; the earlier models that had this system grow stronger did not feature such an active EPAC. Not 100% what caused the GFS to all of a sudden think the EPAC would light up this time, however.

There are a couple of tropical waves in the Caribbean which will be moving into the East Pac over the coming week. That would be the source.

[wxman57]

AS for the wave in the eastern Atlantic, 12Z GFS is looking much more reasonable with its weaker low passing east of Bermuda next week. Could be Emily. Probably only a shipping interest.

[abajan]

Link: https://youtu.be/elV4j1nEiHE

[gatorcane]

Yep looks like the GFS has come to its senses and has caved to the Euro. As noted previously, dry conditions plague the Atlantic MDR so the environment is only marginally conducive, similar to what 95l faced. Difference here is that this system looks to recurve north of the islands where it could encounter better conditions than 95l which was doomed as soon as it moved into the Caribbean.